\ ˈō-pən How to pronounce open (audio) , -pᵊm \
opener\ ˈōp-​nər How to pronounce opener (audio) , ˈō-​pə-​ \; openest\ ˈōp-​nəst How to pronounce openest (audio) , 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 15 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


opened\ ˈō-​pənd How to pronounce opened (audio) , ˈō-​pᵊmd \; opening\ ˈōp-​niŋ How to pronounce opening (audio) , 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



Definition of open (Entry 3 of 3)

2 : open and unobstructed space: such as
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


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


openability \ ˌōp-​nə-​ˈbi-​lə-​tē How to pronounce openability (audio) , ˌō-​pə-​ \ noun
openable \ ˈōp-​nə-​bəl How to pronounce openable (audio) , ˈō-​pə-​ \ adjective

Synonyms & Antonyms for open

Synonyms: Adjective

Synonyms: Verb

Synonyms: Noun

Antonyms: Adjective

Antonyms: Verb

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Choose the Right Synonym for open


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 Schools for students under the age of 16 remain open. Ishaan Tharoor, Washington Post, "Sweden’s coronavirus strategy is not what it seems," 12 May 2020 Even in classrooms for vulnerable children and the children of essential workers that have remained open, the turnout has been low. Isabella Kwai, New York Times, "Human endurance and the Silk Road," 12 May 2020 All four cases remain open and will require the completion of an inspection before any potential enforcement by IOSHA. Tony Cook, Indianapolis Star, "As Indiana nursing home COVID-19 deaths climb to 584, state keeps locations secret," 11 May 2020 The 2,484 centers that remained open could not have more than six children in a classroom. Jessie Balmert, Cincinnati.com, "Coronavirus in Ohio: When will child care centers reopen? DeWine won't say today," 11 May 2020 May 8, 2020 Other county sites, such as the L.A. Arboretum & Botanic Garden in Arcadia and the South Bay Botanic Garden on the Palos Verdes Peninsula, have remained open during the stay-at-home order. Los Angeles Times, "Time to smell the roses. Descanso Gardens to reopen, with new rules," 11 May 2020 How long the testing sites will remain open is unknown. Jordyn Noennig, Milwaukee Journal Sentinel, "Wisconsin coronavirus testing ramps up, with two free sites opening in Milwaukee on Monday," 10 May 2020 So far, Khan has bowed to pressure from the country’s powerful clerical establishment by allowing mosques to remain open, even as the number of new cases has recently increased. NBC News, "Photo: Undertaker waits for body of COVID-19 victim," 9 May 2020 Mercer’s main gardens, color beds, tropical garden, children’s garden and formal garden remain open. Alvaro Montano, Houston Chronicle, "Storey Lake at Mercer Botanic Gardens scheduled to reopen mid-summer," 8 May 2020 Recent Examples on the Web: Verb Amazon, for example, is investing nearly $1.5 billion in a new cargo hub at Cincinnati/Northern Kentucky International Airport, which is expected to open next year with a fleet of 70 planes. Amy Zipkin, New York Times, "As Online Buying Surges, So Do Noisy Cargo Flights," 15 Apr. 2020 Ohio State football’s season is scheduled to open Sept. 5 against Bowling Green. Nathan Baird, cleveland, "Dr. Anthony Fauci says sports can return this summer if ‘nobody comes to the stadium’," 15 Apr. 2020 Reeves said the state needed to open things back up as quickly and as responsibly as possible. Alaa Elassar, CNN, "This is where all 50 states stand on reopening," 15 Apr. 2020 In the Montavilla neighborhood alone, three new restaurants and one bar were supposed to open this spring. Jamie Goldberg, oregonlive, "Coronavirus crisis forces new Portland small businesses to put plans to open on hold," 15 Apr. 2020 Fall football practice typically begins in August, with the season set to open on Labor Day weekend. Creg Stephenson | Cstephenson@al.com, al, "College commissioners to VP Pence: No football before campuses re-open," 15 Apr. 2020 For the virus to attach and infect human cells, spike has to open. Andy Patrizio, Ars Technica, "The coronavirus pandemic turned Folding@Home into an exaFLOP supercomputer," 14 Apr. 2020 The gates to Fair Park are expected to open to vehicles at 8:15 a.m. or later. Nataly Keomoungkhoun, Dallas News, "North Texas Food Bank returns to Fair Park to distribute food with National Guard," 14 Apr. 2020 Modern buildings are generally designed to promote social mixing — from open plan living areas in homes to open offices where many workers share space. Fox News, "Natural light, fresh air could keep coronavirus out of workplaces, scientists suggest," 14 Apr. 2020 Recent Examples on the Web: Noun If the virus is spreading at a low enough rate, the government plans to allow much of the hospitality sector to re-open in July so long as social-distancing measures are implemented. The Economist, "Sad summer Holiday resorts need tourists but don’t want them," 30 May 2020 Problem is, some careless person (attendant?) has left a window open here. Joyce Carol Oates, Harper's Magazine, "Still Life," 25 May 2020 But even cracking one window open just 3 inches can keep this at bay. USA Today, "Coronavirus: How to safely clean your car's interior from COVID-19," 1 May 2020 The first group of stores set to re-open will be in states where shelter in place orders are lifted, namely Texas, Georgia, South Carolina, Tennessee, and Oklahoma. Phil Wahba, Fortune, "Macy’s stores to start slowly re-opening next week but CEO warns retailer will emerge ‘a smaller company’," 30 Apr. 2020 Error 0: Below are the key takeaways from the new initiative for businesses planning to re-open: Flush faucets with cold water and then hot water for 15 minutes on a weekly basis, at a minimum. Rebecca Hennes, Houston Chronicle, "City of Pearland issues new water guidelines for re-opening businesses following pandemic shutdown," 27 Apr. 2020 The village had to build low-cost housing to justify keeping its elementary school open. Noemie Bisserbe, WSJ, "France Says Au Revoir to the Cafe," 7 Feb. 2020 Many large chains had initially hoped to re-open in April, but now everyone from Abercrombie & Fitch to Macy's says they're closed until further notice. Phil Wahba, Fortune, "‘Ugly March’ leads into ‘hideous April’ for retail as sales slip the most they ever have," 15 Apr. 2020 Those bringing the lawsuit want to keep online and by-mail voter registration open until March 27. Patrick Marley, Milwaukee Journal Sentinel, "Democrats sue to extend Wisconsin's deadlines for online voter registration and counting absentee ballots," 18 Mar. 2020

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


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


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


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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Time Traveler for open

Time Traveler

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

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Statistics for open

Last Updated

15 May 2020

Cite this Entry

“Open.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/open. Accessed 3 Jun. 2020.

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More Definitions for open



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

How to pronounce open (audio)

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



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



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
\ ˈō-pən How to pronounce open (audio) \

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


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



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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\ ˈō-pən How to pronounce open (audio) \

Medical Definition of open

 (Entry 1 of 2)

1a(1) : having the skin cracked, cut, or broken so that underlying tissue is exposed abrasions, lacerations, and other open wounds — see also open fracture
(2) of a head injury : marked by fracture or penetration of the skull
b : not involving or encouraging a covering (as by bandages or overgrowth of tissue) or enclosure open treatment of burns
c : 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 infectious 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


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

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


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

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