adjective \ˈō-pən, -pəm\
open·er \ˈōp-nər, ˈō-pə-\ open·est \ˈōp-nəst, ˈō-pə-\

Definition of OPEN

:  having no enclosing or confining barrier :  accessible on all or nearly all sides <cattle grazing on an open range>
a (1) :  being in a position or adjustment to permit passage :  not shut or locked <an open door> (2) :  having a barrier (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>
a :  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
a :  not covered with a top, roof, or lid <an open car> <her eyes were open>
b :  having no protective covering <open wiring> <an open wound>
:  not restricted to a particular group or category of participants <open to the public> <open housing>: as
a :  enterable by both amateur and professional contestants <an open tournament>
b :  enterable by a registered voter regardless of political affiliation <an open primary>
:  fit to be traveled over :  presenting no obstacle to passage or view <the open road> <open country>
:  having the parts or surfaces laid out in an expanded position :  spread out :  unfolded <an open book>
a (1) :  low 13 (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
a :  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 :  not proprietary :  available to third party developers <open source code>
a :  characterized by ready accessibility and usually generous attitude: as (1) :  generous in giving (2) :  willing to hear and consider or to accept and deal with :  responsive (3) :  free from reserve or pretense :  frank
b :  accessible to the influx of new factors (as foreign goods) <an open market>
a :  having openings, interruptions, or spaces <open mesh>: as (1) :  being porous and friable <open soil> (2) :  sparsely distributed :  scattered <open population> (3) of a compound :  having components separated by a space in writing or printing (as opaque projector)
b :  not made up of a continuous closed circuit of channels <the insect circulatory system is open>
a of an organ pipe :  not stopped at the top
b of a string on a musical instrument :  not stopped by the finger
:  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>
a (1) :  characterized by lack of effective regulation of various commercial enterprises <an open town> (2) :  not repressed 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>
:  having been opened by a first ante, bet, or bid <the bidding is open>
of punctuation :  characterized by sparing use especially of the comma
a :  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>
a :  being an incomplete electrical circuit
b :  not allowing the flow of electricity <an open switch>
of a universe :  having insufficient mass to halt expansion gravitationally
open adverb
open·ly \ˈō-pən-lē\ adverb
open·ness \-pə(n)-nəs\ noun

Examples of OPEN

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

Origin of OPEN

Middle English, from Old English; akin to Old High German offan open, Old English ūp up
First Known Use: before 12th century



: 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

opened \ˈō-pənd, ˈō-pəmd\ open·ing \ˈōp-niŋ, ˈō-pə-\

Full Definition of OPEN

transitive verb
a :  to move (as a door) from a closed position
b :  to make available for entry or passage by turning back (as a barrier) or removing (as a cover or an obstruction)
a :  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
a :  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
a :  to make an opening in <opened the boil>
b :  to loosen and make less compact <open the soil>
:  to spread out :  unfold <opened the book>
a :  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
:  to restore or recall (as an order) from a finally determined state to a state in which the parties are free to prosecute or oppose
intransitive verb
:  to become open <the office opened early>
a :  to spread out :  expand <the wound opened under the strain>
b :  to become disclosed <a beautiful vista opened before us>
:  to become enlightened or responsive
:  to give access <the rooms open onto a hall>
:  speak out 2 <finally he opened freely on the subject>
a :  to begin a course or activity
b :  to make a bet, bid, or lead in commencing a round or hand of a card game
:  to provide the opening performance of a show before the main event
open·abil·i·ty \ˌōp-nə-ˈbi-lə-tē, ˌō-pə-\ noun
open·able \ˈōp-nə-bəl, ˈō-pə-\ adjective

Examples of OPEN

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

First Known Use of OPEN

before 12th century



: a competition (such as a major golf tournament or tennis tournament) that allows both professionals and amateurs to participate

the open : 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

Full Definition of OPEN

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

Examples of OPEN

  1. <a daguerreotype of a cowboy whose face is roughened from a hard life in the open>

First Known Use of OPEN

13th century
May 28, 2015
fictioneer Hear it
someone who writes fiction
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