open

adj., v., & n.
—adj.
1 not closed or locked or blocked up; allowing entrance or passage or access.
2 a (of a room, field, or other area) having its door or gate in a position allowing access, or part of its confining boundary removed. b (of a container) not fastened or sealed; in a position or with the lid etc. in a position allowing access to the inside part.
3 unenclosed, unconfined, unobstructed (the open road; open views).
4 a uncovered, bare, exposed (open drain; open wound). b Sport (of a goal mouth or other object of attack) unprotected, vulnerable.
5 undisguised, public, manifest; not exclusive or limited (open scandal; open hostilities).
6 expanded, unfolded, or spread out (had the map open on the table).
7 (of a fabric) not close; with gaps or intervals.
8 a (of a person) frank and communicative. b (of the mind) accessible to new ideas; unprejudiced or undecided.
9 a (of an exhibition, shop, etc.) accessible to visitors or customers; ready for business. b (of a meeting) admitting all, not restricted to members etc.
10 a (of a race, competition, scholarship, etc.) unrestricted as to who may compete. b (of a champion, scholar, etc.) having won such a contest.
11 (of government) conducted in an informative manner receptive to enquiry, criticism, etc., from the public.
12 (foll. by to) a willing to receive (is open to offers). b (of a choice, offer, or opportunity) still available (there are three courses open to us). c likely to suffer from or be affected by (open to abuse).
13 a (of the mouth) with lips apart, esp. in surprise or incomprehension. b (of the ears or eyes) eagerly attentive.
14 Mus. a (of a string) allowed to vibrate along its whole length. b (of a pipe) unstopped at each end. c (of a note) sounded from an open string or pipe.
15 (of an electrical circuit) having a break in the conducting path.
16 (of the bowels) not constipated.
17 (of a return ticket) not restricted as to day of travel.
18 (of a cheque) not crossed.
19 (of a boat) without a deck.
20 (of a river or harbour) free of ice.
21 (of the weather or winter) free of frost.
22 Phonet. a (of a vowel) produced with a relatively wide opening of the mouth. b (of a syllable) ending in a vowel.
23 (of a town, city, etc.) not defended even if attacked.
—v.
1 tr. & intr. make or become open or more open.
2 a tr. change from a closed or fastened position so as to allow access (opened the door; opened the box). b intr. (of a door, lid, etc.) have its position changed to allow access (the door opened slowly).
3 tr. remove the sealing or fastening element of (a container) to get access to the contents (opened the envelope).
4 intr. (foll. by into, on to, etc.) (of a door, room, etc.) afford access as specified (opened on to a large garden).
5 a tr. start or establish or set going (a business, activity, etc.). b intr. be initiated; make a start (the session opens tomorrow; the story opens with a murder). c tr. (of a counsel in a lawcourt) make a preliminary statement in (a case) before calling witnesses.
6 tr. a spread out or unfold (a map, newspaper, etc.). b (often absol.) refer to the contents of (a book).
7 intr. (often foll. by with) (of a person) begin speaking, writing, etc. (he opened with a warning).
8 intr. (of a prospect) come into view; be revealed.
9 tr. reveal or communicate (one's feelings, intentions, etc.).
10 tr. make (one's mind, heart, etc.) more sympathetic or enlightened.
11 tr. ceremonially declare (a building etc.) to be completed and in use.
12 tr. break up (ground) with a plough etc.
13 tr. cause evacuation of (the bowels).
14 Naut. a tr. get a view of by change of position. b intr. come into full view.
—n.
1 (prec. by the) a open space or country or air. b public notice or view; general attention (esp. into the open).
2 an open championship, competition, or scholarship.
Phrases and idioms:
be open with speak frankly to. keep open house see HOUSE. open air (usu. prec. by the) a free or unenclosed space outdoors. open-air (attrib.) out of doors. open-and-shut (of an argument, case, etc.) straightforward and conclusive. open-armed cordial; warmly receptive. open book a person who is easily understood. open day a day when the public may visit a place normally closed to them. open door free admission of foreign trade and immigrants. open-door adj. open, accessible, public. open the door to see DOOR. open-ended having no predetermined limit or boundary. open a person's eyes see EYE. open-eyed
1 with the eyes open.
2 alert, watchful. open-faced having a frank or ingenuous expression. open-handed generous. open-handedly generously. open-handedness generosity. open-hearted frank and kindly. open-heartedness an open-hearted quality. open-hearth process a process of steel manufacture, using a shallow reverberatory furnace. open-heart surgery surgery with the heart exposed and the blood made to bypass it. open house welcome or hospitality for all visitors. open ice ice through which navigation is possible. open letter a letter, esp. of protest, addressed to an individual and published in a newspaper or journal. open market an unrestricted market with free competition of buyers and sellers. open-minded accessible to new ideas; unprejudiced. open-mindedly in an open-minded manner. open-mindedness the quality of being open-minded. open-mouthed with the mouth open, esp. in surprise.
open out
1 unfold; spread out.
2 develop, expand.
3 become communicative.
4 accelerate. open-plan (usu. attrib.) (of a house, office, etc.) having large undivided rooms. open prison a prison with the minimum of physical restraints on prisoners. open question a matter on which differences of opinion are legitimate. open-reel (of a tape recorder) having reels of tape requiring individual threading, as distinct from a cassette. open sandwich a sandwich without a top slice of bread. open sea an expanse of sea away from land. open season the season when restrictions on the killing of game etc. are lifted. open secret a supposed secret that is known to many people. open sesame see SESAME.
open shop
1 a business etc. where employees do not have to be members of a trade union (opp. closed shop).
2 this system. open society a society with wide dissemination of information and freedom of belief. Open University (in the UK) a university that teaches mainly by broadcasting and correspondence, and is open to those without formal academic qualifications.
open up
1 unlock (premises).
2 make accessible.
3 reveal; bring to notice.
4 accelerate esp. a motor vehicle.
5 begin shooting or sounding. open verdict a verdict affirming that a crime has been committed but not specifying the criminal or (in case of violent death) the cause. with open arms see ARM(1).
Derivatives:
openable adj. openness n.
Etymology: OE open