not closed or barred at the time, as a doorway by a door, a window by a sash, or a gateway by a gate: to leave the windows open at night.
(of a door, gate, window sash, or the like) set so as to permit passage through the opening it can be used to close.
having no means of closing or barring: an open portico.
having the interior immediately accessible, as a box with the lid raised or a drawer that is pulled out.
relatively free of obstructions to sight, movement, or internal arrangement: an open floor plan.
constructed so as to be without cover or enclosure on the top or on some or all sides: an open boat.
having relatively large or numerous spaces, voids, or intervals: an open architectural screen; open ranks of soldiers.
perforated or porous: an open texture.
relatively unoccupied by buildings, fences, trees, etc.: open country.
not covered or closed; with certain parts apart: open eyes; open mouth.
without a covering, especially a protective covering; unprotected; unenclosed; exposed:an open wound; open electrical wires.
extended or unfolded: an open newspaper.
without restrictions as to who may participate: an open competition; an open session.
accessible or available to follow: the only course still open to us.
not taken or filled; not preempted; available; vacant: Which job is open?
ready for or carrying on normal trade or business: The new store is now open. The office is open on Saturdays.
not engaged or committed: Have you any open time on Monday?
accessible, as to appeals, ideas, or offers: to be open to suggestion.
exposed to general view or knowledge; existing, carried on, etc., without concealment: open disregard of the rules.
acting publicly or without concealment, as a person.
unreserved, candid, or frank, as persons or their speech, aspect, etc.: an open manner.
generous, liberal, or bounteous: to give with an open hand.
liable or subject: open to question; open to retaliation.
undecided; unsettled: several open questions.
without effective or enforced legal, commercial, or moral regulations: an open town.
unguarded by an opponent: an open wide receiver.
noting the part of the sea beyond headlands or enclosing areas of land: to sail on the open seas.
free of ice, as a body of water or a seaport.
free of navigational hazards: an open coast.
(of a seaport) available for foreign trade; not closed by government regulations or by considerations of health.
(of a microphone) in operation; live.
(of a delimiting punctuation mark) occurring at the beginning of a group of words or characters that is set off, as from surrounding text: open parenthesis; open quotes.: Compare close (def. 51).
not yet balanced or adjusted, as an account.
not constipated, as the bowels.
Linguistics. (of a class of items) readily admitting new members, as the class of nouns, verbs, or adjectives (opposed to closed).
(of type) in outline form.
widely spaced or leaded, as printed matter.
(of an organ pipe) not closed at the far end.
(of a string) not stopped by a finger.
(of a note) produced by such a pipe or string or, on a wind instrument, without the aid of a slide, key, etc.
(of an interval) containing neither endpoint.
(of a set) consisting of points having neighborhoods wholly contained in the set, as the set of points within a circle.
(of a map from one topological space to another) having the property that the image of an open set is an open set.
free from frost; mild or moderate: an open winter.
Animal Husbandry. (of a female animal) not pregnant.
Textiles. (of a fabric or weave) so loosely woven that spaces are visible between warp and filling yarns.
to move (a door, window sash, etc.) from a shut or closed position so as to admit of passage.
to render (a doorway, gateway, window, etc.) unobstructed by moving a door, window sash, etc., away from it.
to render the interior of (a box, drawer, etc.) readily accessible.
to clear (a passage, channel, etc.) of obstructions.
to clear (areas or passages in the body).
to give access to; make accessible or available, as for use: to open a port for trade.
to establish for business purposes or for public use: to open an office.
to set in action, begin, start, or commence (sometimes followed by up): to open a campaign.
to uncover, lay bare, or expose to view.
to expand, unfold, or spread out: to open a map.
to make less compact, less closely spaced, or the like: to open ranks.
to disclose, reveal, or divulge.
to render accessible to knowledge, enlightenment, sympathy, etc.: to open one's mind.
to cut, blast, or break into: to open a safe with nitro.
to make or produce (an opening) by cutting or breaking, or by pushing aside or removing obstructions: to open a way through a crowd.
to make an incision or opening in: to open a boil.
to recall or revoke (a judgment, decree, etc.) for the purpose of allowing further contest or delay.
to make the first statement of (a case) to the court or jury.
Cards. to begin a hand by making (the first bid), placing (the first bet), or playing (a given card or suit) as the lead.
Nautical. to sail (a course) so that the apparent location of a distant fixed object changes with relation to a nearer fixed object (sometimes followed by out).
to become open, as a door, building, box, or enclosure.
to afford access: a door that opens into a garden.
to have an opening, passage, or outlet: The room opens into a corridor.
(of a building, theater, etc.) to open its doors to the public: The museum opens at one o'clock.
to begin a session or term, as a school.
to begin a season, series of performances, or tour, as a theatrical company: The play will open in Boston.
to begin, start, or commence an activity: The game opened with the national anthem.
to part, or seem to part, so as to allow or reveal a passage: At last the cliffs opened to show us that we were heading for the sea.
to become disclosed or revealed.
to come into view; become more visible or plain.
to become receptive to knowledge, sympathy, etc., as the mind.
to disclose or reveal one's knowledge, thoughts, feelings, etc.
to unfold or expand, as a blossom, so as to reveal the interior.
to spread out or expand, as the hand or a fan.
to spread apart or separate, as pages of a book, newspaper, etc.: Open to page 32.
to spread or come apart; burst: The wound opened.
to become less compact, less closely spaced, or the like: The ranks began to open.
Cards. to make the first bet, bid, or lead in beginning a hand.
Hunting. (of hounds) to begin to bark, as on the scent of game.
an open or clear space.
the open air.
the open water, as of the sea.
an opening or aperture.
an opening or opportunity.
a contest or tournament in which both amateurs and professionals may compete, especially in golf and tennis.
the unenclosed or unobstructed country.
the outdoors: Vacations in the open are fine for the entire family.
the condition of being unconcealed, recognized, or publicly known: The scandal is now out in the open.
to become or make open.
to expand, especially before the eye: A breathtaking panorama opened up as we reached the top of the hill.
to achieve the initial development of: to open up a business office; to open up trade with China.
Slang. to increase speed or the speed of (a vehicle).
- o·pen·ly, adverb
- o·pen·ness, noun
- half-o·pened, adjective
- pre·o·pen, verb (used with object)
- self-o·pened, adjective
- sem·i·o·pen, adjective
- sem·i·o·pen·ly, adverb
- un·o·pened, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use open in a sentence
The contributions of Murray and Nikola Jokić go without saying, and when one got going, it opened up things for the other, because of how the Clippers went about trapping and doubling.Bam Adebayo Is Making Plays, Denver Is Making Us Look Bad, And The Lakers May Need To Make Some Adjustments | Chris Herring (firstname.lastname@example.org) | September 17, 2020 | FiveThirtyEight
Forage is focused on partnering with large companies that employ upwards of 1,000 students per year via internships to help open up new pipelines.Forage, formerly InsideSherpa, raises $9.3 million Series A for virtual work experiences | Natasha Mascarenhas | September 17, 2020 | TechCrunch
Jefferson County, the most populous one in the Bluegrass State, will have eight polling locations open on Election Day, and your state may decide to do something similar.Why you should vote as early as possible (and how to do it) | John Kennedy | September 17, 2020 | Popular-Science
Outside of New York, the publisher opened its London bureau in 2014, where it now has over 100 staffers.‘We’re about hiring journalists’: Insider Inc. launches third global news hub in Singapore | Lucinda Southern | September 17, 2020 | Digiday
I would love to have the country opened up and just raring to go by Easter.Timeline: The 124 times Trump has downplayed the coronavirus threat | Aaron Blake, JM Rieger | September 17, 2020 | Washington Post
When it became too crowded, they moved her into an open casket on the street.New York’s Most Tragic Ghost Loves Minimalist Swedish Fashion | Nina Strochlic | January 8, 2015 | THE DAILY BEAST
Now it can't open on my phone due to what appears to be software incompatibility.
Some of them would open up deep splits in core Democratic constituencies.
And of course, Rod, being Rod, goes for it a hundred percent; his mouth drops open and he says, ‘What?’The Story Behind Lee Marvin’s Liberty Valance Smile | Robert Ward | January 3, 2015 | THE DAILY BEAST
open-carry activists are known for baiting cops into on-camera arguments about the Second Amendment and state laws.Texas Gun Slingers Police the Police—With a Black Panthers Tactic | Brandy Zadrozny | January 2, 2015 | THE DAILY BEAST
Let them open their minds to us, let them put upon permanent record the significance of all their intrigues and manœuvres.The Salvaging Of Civilisation | H. G. (Herbert George) Wells
The doors (Indian bungalows have hardly any windows, each door being half glass) were open front and back.The Red Year | Louis Tracy
It was close upon twelve o'clock, and the "Rooms" had been open to the public for two hours.Rosemary in Search of a Father | C. N. Williamson
Worst danger zone, the open sea, now traversed, but on land not yet out of the wood.Gallipoli Diary, Volume I | Ian Hamilton
To think,” said the younger Englishwoman to her sister, “of this wee mite travelling about in an open motor!The Joyous Adventures of Aristide Pujol | William J. Locke
British Dictionary definitions for open
not closed or barred: the door is open
affording free passage, access, view, etc; not blocked or obstructed: the road is open for traffic
not sealed, fastened, or wrapped: an open package
having the interior part accessible: an open drawer
extended, expanded, or unfolded: an open newspaper; an open flower
ready for business: the shops are open
able to be obtained; available: the position advertised last week is no longer open
unobstructed by buildings, trees, etc: open countryside
free to all to join, enter, use, visit, etc: an open competition
unengaged or unoccupied: the doctor has an hour open for you to call
See open season
not decided or finalized: an open question
ready to entertain new ideas; not biased or prejudiced: an open mind
unreserved or candid: she was very open in her description
liberal or generous: an open hand
extended or eager to receive (esp in the phrase with open arms)
exposed to view; blatant: open disregard of the law
liable or susceptible: you will leave yourself open to attack if you speak
(of climate or seasons) free from frost; mild
free from navigational hazards, such as ice, sunken ships, etc: open water
US without legal restrictions or enforceable regulations, esp in relation to gambling, vice, etc: an open town
without barriers to prevent absconding: an open prison
having large or numerous spacing or apertures: open ranks
full of small openings or gaps; porous: an open texture
printing (of type matter) generously leaded or widely spaced
(of a violin or guitar string) not stopped with the finger
(of a pipe, such as an organ pipe) not closed at either end
(of a note) played on such a string or pipe
in operation; active: an open account
unrestricted; unlimited: open credit; open insurance cover
See open cheque
(of a return ticket) not specifying a date for travel
(of a goal, court, etc) unguarded or relatively unprotected: the forward missed an open goal
(of a stance, esp in golf) characterized by the front of the body being turned forward
(of a wound) exposed to the air
(esp of the large intestine) free from obstruction
undefended and of no military significance: an open city
denoting a vowel pronounced with the lips relatively wide apart
denoting a syllable that does not end in a consonant, as in pa
chess (of a file) having no pawns on it
maths (of a set) containing points whose neighbourhood consists of other points of the same set: points inside a circle are an open set
computing (of software or a computer system) designed to an internationally agreed standard in order to allow communication between computers, irrespective of size, maufacturer, etc
to move or cause to move from a closed or fastened position: to open a window
(when intr, foll by on or onto) to render, be, or become accessible or unobstructed: to open a road; to open a parcel; the door opens into the hall
(intr) to come into or appear in view: the lake opened before us
(tr) to puncture (a boil) so as to permit drainage
to extend or unfold or cause to extend or unfold: to open a newspaper
to disclose or uncover or be disclosed or uncovered: to open one's heart
to cause (the mind) to become receptive or (of the mind) to become receptive
to operate or cause to operate: to open a shop
(when intr, sometimes foll by out) to make or become less compact or dense in structure: to open ranks
to set or be set in action; start: to open a discussion; to open the batting
(tr) to arrange for (a bank account, savings account, etc) usually by making an initial deposit
to turn to a specified point in (a book, magazine, etc): open at page one
law to make the opening statement in (a case before a court of law)
(intr) cards to bet, bid, or lead first on a hand
the open any wide or unobstructed space or expanse, esp of land or water
See open air
sport a competition which anyone may enter
bring into the open to make evident or public
come into the open to become) evident or public
- See also open up
- openable, adjective
- openly, adverb
- openness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Other Idioms and Phrases with open
In addition to the idioms beginning with open
- open and aboveboard
- open and shut
- open book
- open doors
- open fire
- open house, keep
- open mind
- open one's eyes
- open one's heart to
- open one's mouth
- open question
- open season on
- open secret
- open the door to
- open up
- open with
- keep a weather eye (open)
- keep one's eyes open
- lay open
- leave open
- leave the door open
- not open one's mouth
- out in the open
- throw open
- wide open
- with one's eyes open
- with open arms
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.