open

adjective
\ ˈō-pən , -pᵊm\
opener\ ˈōp-​nər , ˈō-​pə-​ \; openest\ ˈōp-​nəst , ˈō-​pə-​ \

Definition of open

 (Entry 1 of 3)

1 : having no enclosing or confining barrier : accessible on all or nearly all sides cattle grazing on an open range
2a(1) : being in a position or adjustment to permit passage : not shut or locked an open door
(2) : having a barrier (such as a door) so adjusted as to allow passage the house was open
b : having the lips parted stood there with his mouth wide open
c : not buttoned or zipped an open shirt
3a : completely free from concealment : exposed to general view or knowledge their hostilities eventually erupted with open war
b : exposed or vulnerable to attack or question : subject open to doubt
c : being an operation or surgical procedure in which an incision is made such that the tissues are fully exposed
4a : not covered with a top, roof, or lid an open car her eyes were open
b : having no protective covering open wiring
5a : having the skin cracked, cut, or broken so that underlying tissue is exposed abrasions, lacerations, and other open wounds — see also open fracture
b of a head injury : marked by fracture or penetration of the skull
6 : not restricted to a particular group or category of participants open to the public open housing : such as
a : enterable by both amateur (see amateur sense 1) and professional (see professional entry 1 sense 2a) contestants an open tournament
b : enterable by a registered voter regardless of political affiliation an open primary
7 : fit to be traveled over : presenting no obstacle to passage or view the open road open country
8 : having the parts or surfaces laid out in an expanded position : spread out : unfolded an open book
9a(1) : low sense 13 an open vowel
(2) : formed with the tongue in a lower position Italian has an open and a close e
b(1) : having clarity and resonance unimpaired by undue tension or constriction of the throat an open vocal tone
(2) of a tone : produced by an open string or on a wind instrument by the lip without the use of slides, valves, or keys
10a : available to follow or make use of the only course open to us
b : not taken up with duties or engagements keep an hour open on Friday
c : not finally decided : subject to further consideration the salary is open an open question
d : available for a qualified applicant : vacant the job is still open
e : remaining available for use or filling until canceled an open order for more items
f : available for future purchase these items are in open stock
g : available for breeding : not now pregnant an open heifer
h computers : not proprietary : available to third party developers But while IBM pushes Notes, a proprietary technology created in the 1980s, a raft of new and much smaller rivals is plying the "open" technology of the 1990s: software on the World Wide Web, the fastest growing part of the Internet.— Bart Ziegler — compare open-source
11a : characterized by ready accessibility and usually generous attitude: such as
(1) : generous in giving
(2) : willing to hear and consider or to accept and deal with : responsive open to an offer open to suggestion
(3) : free from reserve or pretense : frank was open about his personal life
(4) of a relationship : not restricted to one partner at a time by mutual agreement — see also open marriage
b : accessible to the influx of new factors (such as foreign goods) an open market
12a : having openings, interruptions, or spaces open mesh : such as
(1) : being porous (see porous sense 2a) and friable open soil
(2) : sparsely distributed : scattered open population
(3) of a compound : having components (see component entry 1 sense 1) separated by a space in writing or printing (such as opaque projector)
b : not made up of a continuous closed circuit (see circuit entry 1 sense 2a) of channels the insect circulatory system is open
13a of an organ pipe : not stopped at the top
b of a string on a musical instrument : not stopped by the finger
14 : being in operation an open microphone especially : ready for business, patronage, or use the store is open from 9 to 5 the new highway will be open next week
15a(1) : characterized by lack of effective regulation of various commercial enterprises (see enterprise sense 2) an open town
(2) : not repressed (see repress sense 1) by legal controls open gambling
b : free from checking or hampering restraints an open economy
c : relatively unguarded by opponents passed to an open teammate
16 : having been opened by a first ante, bet, or bid the bidding is open
17 of punctuation : characterized by sparing use especially of the comma when possible without causing misinterpretation
18a : containing none of its endpoints an open interval
b : being a set or composed of sets each point of which has a neighborhood all of whose points are contained in the set the interior of a sphere is an open set
19a : being an incomplete electrical circuit
b : not allowing the flow of electricity an open switch
20 of a universe : having insufficient mass (see mass entry 2 sense 1c) to halt expansion gravitationally

open

verb
opened\ ˈō-​pənd , ˈō-​pᵊmd \; opening\ ˈōp-​niŋ , ˈō-​pə-​ \

Definition of open (Entry 2 of 3)

transitive verb

1a : to move (something, such as a door) from a closed position
b : to make available for entry or passage by turning back (something, such as a barrier) or removing (something, such as a cover or an obstruction)
2a : to make available for or active in a regular function open a new store
b : to make accessible for a particular purpose opened new land for settlement
c : to initiate access to (a computer file) prior to use
3a : to disclose or expose to view : reveal
b : to make more discerning or responsive : enlighten must open our minds to the problems
c : to bring into view or come in sight of by changing position
4a : to make an opening in opened the boil
b : to loosen and make less compact open the soil
5 : to spread out : unfold opened the book
6a : to enter upon : begin opened the meeting
b : to commence action in a card game by making (a first bid), putting a first bet in (the pot), or playing (a card or suit) as first lead
7 : to restore or recall (something, such as an order) from a finally determined state to a state in which the parties are free to prosecute or oppose

intransitive verb

1 : to become open the office opened early
2a : to spread out : expand the wound opened under the strain
b : to become disclosed a beautiful vista opened before us
3 : to become enlightened or responsive
4 : to give access the rooms open onto a hall
5 : speak out sense 2 finally he opened freely on the subject
6a : to begin a course or activity
b : to make a bet, bid, or lead in commencing a round or hand of a card game
7 : to provide the opening performance of a show before the main event

open

noun

Definition of open (Entry 3 of 3)

1 : opening
2 : open and unobstructed space: such as
a : open air
b : open water
3 : an open contest, competition, or tournament
4 : a public or unconcealed state or position

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Other Words from open

Adjective

open adverb
openly \ ˈō-​pən-​lē \ adverb
openness \ ˈō-​pə(n)-​nəs \ noun

Verb

openability \ ˌōp-​nə-​ˈbi-​lə-​tē , ˌō-​pə-​ \ noun
openable \ ˈōp-​nə-​bəl , ˈō-​pə-​ \ adjective

Synonyms & Antonyms for open

Synonyms: Adjective

clear, cleared, free, unclogged, unclosed, unobstructed, unstopped

Synonyms: Verb

unclose

Synonyms: Noun

nature, open air, out-of-doors, outdoors, wild, wilderness

Antonyms: Adjective

blocked, clogged, closed, jammed, obstructed, plugged, shut, stopped, stuffed, uncleared

Antonyms: Verb

close, shut

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Choose the Right Synonym for open

Adjective

frank, candid, open, plain mean showing willingness to tell what one feels or thinks. frank stresses lack of shyness or secretiveness or of evasiveness from considerations of tact or expedience. frank discussions candid suggests expression marked by sincerity and honesty especially in offering unwelcome criticism or opinion. a candid appraisal open implies frankness but suggests more indiscretion than frank and less earnestness than candid. open in saying what they think plain suggests outspokenness and freedom from affectation or subtlety in expression. plain talk

liable, open, exposed, subject, prone, susceptible, sensitive mean being by nature or through circumstances likely to experience something adverse. liable implies a possibility or probability of incurring something because of position, nature, or particular situation. liable to get lost open stresses a lack of barriers preventing incurrence. a claim open to question exposed suggests lack of protection or powers of resistance against something actually present or threatening. exposed to infection subject implies an openness for any reason to something that must be suffered or undergone. all reports are subject to review prone stresses natural tendency or propensity to incur something. prone to delay susceptible implies conditions existing in one's nature or individual constitution that make incurrence probable. very susceptible to flattery sensitive implies a readiness to respond to or be influenced by forces or stimuli. unduly sensitive to criticism

Examples of open in a Sentence

Adjective

The door suddenly swung open. You left the blinds wide open. The meat was roasted over an open fire. I was so tired that I couldn't keep my eyes open. Don't chew with your mouth open. staring with her eyes wide open There's already an open jar of pickles in the refrigerator. They kept the road open throughout the winter.

Verb

This door is hard to open. Open the door!” shouted the police officer. Would you mind if I opened a window? The car door opened and a beautiful woman stepped out. The door opened and closed so quietly that I didn't notice he had come in the room. This drawer is stuck. It just won't open! She comes home, turns on the TV, and starts opening her mail. She opened her eyes and smiled at me. I opened my umbrella and stepped out into the rain. Open your mouth wide for me,” said the dentist.

Noun

a daguerreotype of a cowboy whose face is roughened from a hard life in the open
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Recent Examples on the Web: Adjective

It was also complicated because [Hampton Court Palace] was open to the public. Chloe Foussianes, Town & Country, "The Favourite's Production Designer Explains How They Managed to Film with All Those Rabbits," 12 Feb. 2019 The remaining parts are either purchased on the open market or cannibalized from non-operational Tiger IIs, of which Iran has nearly 100. Kyle Mizokami, Popular Mechanics, "Iran’s Aging American-Made Jets Could Fly Through the 2040s," 11 Feb. 2019 That shift from the courts to statehouses, Congress and the open market has revealed divisions among the leagues in how to approach the inevitability of expanded legal betting. Wayne Parry, The Seattle Times, "US sports leagues split on how to monetize sports betting," 4 Feb. 2019 The House Beautiful Whole Home Concept House will be open to the public from Friday, October 18th, through November 2nd, and proceeds will benefit the Nashville Symphony. House Beautiful, "The 2019 Whole Home Is Coming To Nashville," 30 Jan. 2019 The newly-open Chinese market will reward such innovation. James C. Collins Jr., WSJ, "China Opens the Door to U.S. GMOs," 24 Jan. 2019 Let’s keep the conversation open for listeners to interpret it for themselves. Danny Murphy, Glamour, "If You Love 'Thank U, Next,' Just Wait Until You Meet Songwriter Tayla Parx," 3 Dec. 2018 The most important thing to remember when going through this is to keep yourself open to your new surroundings. Fresh U, Teen Vogue, "How To Cope With Culture Shock In College," 13 Nov. 2018 In an interview, OnePlus CEO Pete Lau told me (through a translator) that getting a phone on Verizon’s network wasn’t possible for OnePlus until Verizon launched its certification program for open-market devices or phones not sold by Verizon. Dan Seifert, The Verge, "The OnePlus 6T might be the company’s big break in America," 29 Oct. 2018

Recent Examples on the Web: Verb

But to all the MAGA eggs currently opening Twitter to take aim at me, consider, too, that opposition to the State of the Union is not Trump-specific, or even new. Michelle Ruiz, Vogue, "America Doesn't Need the State of the Union Address Anymore—Especially Not From Trump," 5 Feb. 2019 Rather than opening its own stores overseas, Walmart wants to become a controlling shareholder in strong domestic players. Carol Ryan, WSJ, "Walmart’s Plan B for its U.K. Checkout," 4 Feb. 2019 The entryway leads to a 21-foot dining room with long French doors that open onto a terrace and garden. Maya Mcdowell, House Beautiful, "The 1920s New York Mansion of the Vanderbilts Is for Sale," 2 Feb. 2019 McPhee is set to star in the musical, Waitress, which will premiere at London's Adelphi Theatre on February 8 and officially open on March 7, Playbill reports. Erica Gonzales, Harper's BAZAAR, "Meghan Markle and Katharine McPhee Did Musicals Together as Kids," 1 Feb. 2019 The Pelicans responded by opening the season with a surprisingly lopsided victory at Houston and started 4-0 before a series of injuries appeared to undermine them. Brett Martel, The Seattle Times, "Agent: Anthony Davis tells New Orleans that he wants a trade," 29 Jan. 2019 Local activists believe race played a factor in the shooting, and witnesses said that Covey, a white officer, simply opened fire after seeing a black man with a gun, despite people screaming that Roberson was a security guard. P.r. Lockhart, Vox, "A black security guard caught a shooting suspect — only to be shot by police minutes later," 23 Jan. 2019 Thanks for opening the conversation and like...to everyone for to me about it. Carolyn Twersky, Seventeen, "All the Backlash Ariana Grande Has Faced Following the “7 Rings” Music Video," 22 Jan. 2019 The Twitter account, which was opened over the weekend, has more than 98,000 followers. Jewel Wicker, Teen Vogue, "Saudi Teen Rahaf Mohammed al-Qunun May Get Asylum From Australia After Fleeing Her Family's Alleged Mistreatment," 8 Jan. 2019

Recent Examples on the Web: Noun

The cold open was just the beginning of SNL's all-in approach to the Kavanaugh hearings. Zoe Weiner, Glamour, "Matt Damon Played a Belligerent Brett Kavanaugh on SNL's 44th Season Premiere," 30 Sep. 2018 The whole space has an open, flowing layout, to encourage seamless wandering. Elise Taylor, Vogue, "A First Look at the Faena Bazaar, Miami Beach’s New Design Destination," 3 Dec. 2018 The Ropes Mansion is open between 12 p.m.-4 p.m. on weekends from May through late October. Alyssa Fiorentino, House Beautiful, "You Need To Know The Real Story Behind Allison's House From Hocus Pocus," 17 Oct. 2018 In the show's cold open, Kimmel presented Daniels with a Donald Trump puppet and urged her to show what Trump had done with it. Kelly Lawler, USA TODAY, "Stormy Daniels doesn't confirm or deny alleged Trump affair on 'Kimmel'," 31 Jan. 2018 In contrast to Carlsen’s noted ability to finish off end games, Caruana is said to intensely focus on the opens and search for an early edge. Andrew Beaton, WSJ, "Magnus Carlsen vs. the American in a Chess Championship for the Ages," 9 Nov. 2018 The Fake News Media, the true Enemy of the People, must stop the open & obvious hostility & report the news accurately & fairly. Stavros Agorakis, Vox, "Poll: GOP voters blame news for division in America; Democrats blame Trump," 1 Nov. 2018 Eat it here: Superdawg in Chicago (open until 1 a.m.); Curry 36 in Berlin (open until 5 a.m.); Bæjarins Beztu Pylsur in Reykjavík (open until 1 a.m.). Cnt Editors, Condé Nast Traveler, "A Debatable Encyclopedia of Drunk Food," 1 Oct. 2018 The Spy Who Loved Me’ In one of the most iconic cold opens of the franchise, 007 takes out a handful of would-be assassins while swooshing down the Austrian Alps. WSJ, "A Nearly Nude Take on James-Bond Style," 6 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'open.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of open

Adjective

before the 12th century, in the meaning defined at sense 1

Verb

before the 12th century, in the meaning defined at transitive sense 1a

Noun

13th century, in the meaning defined at sense 1

History and Etymology for open

Adjective, Verb, and Noun

Middle English, from Old English; akin to Old High German offan open, Old English ūp up

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Statistics for open

Last Updated

21 Feb 2019

Look-up Popularity

Time Traveler for open

The first known use of open was before the 12th century

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More Definitions for open

open

noun

Financial Definition of open

What It Is

In the stock markets, open refers to the beginning of the trading day or the price of a security at the beginning of the trading day.

How It Works

The New York Stock Exchange has the most famous opening bell. At 9:30 am Eastern time, it rings. At that time, the last trading price for each security on the exchange the day before (the closing price) becomes the opening price, or the open.

Why It Matters

The open is the start of a new day, though it is important to note that that doesn't necessarily mean trading hasn't been going on right before the open. After-hours markets remain open as do other exchanges in other countries and time zones, which provides opportunity for the price to change right up until the open in many cases.

Source: Investing Answers

open

adjective

English Language Learners Definition of open

 (Entry 1 of 3)

: not covering an opening
: having an opening that is not covered
: not sealed or locked

open

verb

English Language Learners Definition of open (Entry 2 of 3)

: to move (a door, window, etc.) so that an opening is no longer covered
: to move and no longer cover an opening
: to cause (something) to no longer be covered, sealed, or blocked

open

noun

English Language Learners Definition of open (Entry 3 of 3)

: a competition (such as a major golf tournament or tennis tournament) that allows both professionals and amateurs to participate
: an area or place without walls, barriers, etc. : an area or place that is not covered or enclosed
: a situation in which something (such as a feeling) is no longer hidden or kept secret

open

adjective
\ ˈō-pən \

Kids Definition of open

 (Entry 1 of 3)

1 : not shut or blocked : not closed an open window open books
2 : not sealed, locked, or fastened an open zipper There's an open bottle of ketchup in the refrigerator.
3 : easy to enter, get through, or see open country
4 : ready to consider appeals or ideas an open mind
5 : not drawn together : spread out an open flower open umbrellas
6 : not enclosed or covered an open boat an open fire
7 : not secret : public They have an open dislike for one another.
8 : to be used, entered, or taken part in by all an open meeting It was an open race—any number of dogs could be entered.— John Reynolds Gardiner, Stone Fox
9 : not decided or settled an open question

Other Words from open

openly adverb
openness noun

open

verb
opened; opening

Kids Definition of open (Entry 2 of 3)

1 : to change or move from a shut condition Sit down and open a book. The door opened. She opened her eyes.
2 : to clear by or as if by removing something in the way Workers were sent to open a road blocked with snow.
3 : to make or become ready for use They plan to open a store. The office opens at eight.
4 : to give access The rooms open onto a hall.
5 : begin sense 1, start Police have opened an investigation. They opened fire on the enemy.

Other Words from open

opener \ ˈō-​pə-​nər , ˈōp-​nər \ noun

open

noun

Kids Definition of open (Entry 3 of 3)

: space that is not enclosed or covered : outdoors Some slept in a cabin while others slept in the open.

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open

adjective
\ ˈō-pən \

Medical Definition of open

 (Entry 1 of 2)

1a : not covered, enclosed, or scabbed over an open lesion an open running ulcer
b : not involving or encouraging a covering (as by bandages or overgrowth of tissue) or enclosure open treatment of burns
c : relating to or being a compound fracture
d : being an operation or surgical procedure in which an incision is made such that the tissues and organs are fully exposed — compare open-heart
2 : shedding the infective agent to the exterior open tuberculosis — compare closed sense 3
3a : unobstructed by congestion or occlusion open sinuses
b : not constipated open bowels
4 : using a minimum of physical restrictions and custodial restraints on the freedom of movement of the patients or inmates an open psychiatric ward

open

verb
opened; opening

Medical Definition of open (Entry 2 of 2)

transitive verb

1a : to make available for entry or passage by removing (as a cover) or clearing away (as an obstruction)
b : to free (a body passage) of congestion or occlusion an inhalator for opening congested nasal passages open clogged arteries
2 : to make one or more openings in opened the boil

intransitive verb

: to spread out the wound opened

open

adjective

Legal Definition of open

 (Entry 1 of 2)

1 : exposed to general view or knowledge : free from concealment an open, notorious, continuous, and adverse use of the property an open and obvious danger

Note: When a defect, hazard, or condition is open such that a reasonable person under the circumstances should have recognized the danger posed by it, a defendant is usually relieved of liability for failure to warn.

2 : not restricted to a particular group or category of participants specifically : enterable by a registered voter regardless of political affiliation an open primary
3a : being in effect or operation an open mine a bench warrant still open
b : available for use an open toll road
c : not finally determined, decided, or settled : subject to further consideration an open question
d : remaining effective or available for use until canceled an open insurance contract
4 : not repressed or regulated by legal controls a state with open gambling

open

verb
opened; opening

Legal Definition of open (Entry 2 of 2)

transitive verb

1 : to begin the process of open the succession
2a : to make the statement by which the trial of (a case) is begun and put before the court
b : to be the first to speak in summing up or arguing (a case)
3 : to restore or recall (as an order, rule, or judgment) from a finally determined state to a state in which the parties are free to prosecute or oppose by further proceedings

intransitive verb

1 : to begin action : commence on some course or activity the stock opened at par
2 : to begin the trial of a case defendant…has the option of presenting an opening statement immediately after plaintiff opens— J. H. Friedenthal et al.

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More from Merriam-Webster on open

Thesaurus: All synonyms and antonyms for open

Spanish Central: Translation of open

Nglish: Translation of open for Spanish Speakers

Britannica English: Translation of open for Arabic Speakers

Comments on open

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very full or close together

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