open

Open or unobstructed space; an exposed location.

Adjective

  1. Physically unobstructed, uncovered, etc.
    • Come in – the door's open.
    • The ice has cleared and the channel is open again.

    1. Able to have something pass through or along it.

    2. Not covered, sealed, etc.; having an opening or aperture showing what is inside.

      • The jewellery box was lying open.
      • Don't just stand there with your mouth open!
      • Along the street ran an open sewer.

    3. Not physically drawn together, folded or contracted.

      • She greeted them with open arms.
      • The book was open at page 23.
      • an open hand; an open flower; an open (loosely woven) fabric

    4. Of a space, free of objects and obstructions.

      • It was a large, open room.
      • Most of the site was occupied by huts, but there was an open area in the centre.
      • Soon we left the forest behind and we were out in open country.

    5. (medicine) Resulting from an incision, puncture or any other process by which the skin no longer protects an internal part of the body.

      • an open fracture

    6. (sometimes proscribed) Unlocked or unlatched but not physically open.

    7. (engineering, gas and liquid flow, of valve or damper) In a position allowing fluid to flow.

    8. Of a sandwich, etc.: composed of a single slice of bread with a topping.

      • open sandwich
      • Starry food is fun to make. You can buy bright yellow American mustard (which isn’t too strong!) in squeezy bottles and pipe stars on to hot dogs and open burgers or sandwiches. - 2001, Jennie Walters, Caz’s Birthday...
      • When the burgers are ready, place them on the toasted rolls with the romaine lettuce leaves and top with the salsa. Serve as open burgers. - 2012, Jo McAuley, “[Meat and Poultry] Turkey Burgers with Spicy Salsa”, in...

      Synonyms: open-face open-faced

    9. (now regional) Not of a quality to prevent communication, as by closing waterways, blocking roads, etc.; hence, not frosty or inclement; mild; used of the weather or the climate.

      • an open winter
      • He desires me to tell you that the present open weather induces him to accept Mr Vernon's invitation to prolong his stay in Sussex that they may have some hunting together. - c. 1794, Jane Austen, Lady Susan:
  2. Able to be used or interacted with in some way.
    • Your bank account is now open.
    • Phone lines open at 10 pm.
    • This is the only option open to us.

    1. (not comparable) Available for use or operation.

    2. (not comparable) Actively conducting or prepared to conduct business.

      • Banks are not open on bank holidays.
      • Several new shops have opened in Market Street.

    3. (not comparable) Allowing entrance to visitors or the public.

      • I hereby declare this fete open.
      • The school has an open day on Saturday.

    4. (comparable) Receptive.

      • I am open to new ideas.
      • Wherefore if Demetrius […] have a matter against any man, the law is open and there are deputies. - 1611, The Holy Bible, […] (King James Version), London: […] Robert Barker, […], →OCLC, Acts 19:38:
      • A U.K. survey found attitudes toward public transit had been set back by two decades, with only 43% of drivers open to using their car less, even if public transport improves. - 2021 April 2, Ciara Nugent, “Can Public...

    5. (comparable, with 'to') Susceptible or vulnerable (to the stated means).

      • open to question; open to attack; open to criticism
      • The service that I truly did his life, / Hath left me open to all injuries. - c. 1596–1599 (date written), William Shakespeare, “The Second Part of Henry the Fourth, […]. Epilogue.”, in Mr. William Shakespeares...

    6. (computing, not comparable, of a file, document, etc.) In current use; connected to as a resource.

      • I couldn't save my changes because another user had the same file open.

    7. (computing, of a program or application, especially one with a screen-based interface) Running.

      • You're getting short of memory because you have too many apps open.
  3. Not hidden or restricted.
    • It is a blatant example of open criminality.
    • His thefts were too open. - c. 1597 (date written), William Shakespeare, “The Merry Wiues of Windsor”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and...
    • That I may find him, and with secret gaze / Or open admiration him behold. - 1667, John Milton, “Book III”, in Paradise Lost. […], London: […] [Samuel Simmons], and are to be sold by Peter Parker […]; [a]nd by Robert...

    1. Not concealed; overt.

    2. Of a person, not concealing their feelings, opinions, etc.; candid, ingenuous.

      • Nowadays people are more open about their sexuality.
      • 1731-1735, Alexander Pope, Moral Essays with aspect open, shall erect his head
      • The Moor is of a free and open nature. - c. 1603–1604 (date written), William Shakespeare, “The Tragedie of Othello, the Moore of Venice”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio),...

    3. (not comparable) Public.

      • He published an open letter to the governor on a full page of The New York Times.

    4. (law, of correspondence) Written or sent with the intention that it may made public or referred to at any trial, rather than by way of confidential private negotiation for a settlement.

      • You will observe that this is an open letter and we reserve the right to mention it to the judge should the matter come to trial.

    5. (not comparable) With open access, of open science, or both.

      • We hope that all aspects of the project will be open rather than paywalled.

    6. (computing, education) Made public, usable with a free licence and without proprietary components.

      • Since the launch early last year of […] two Silicon Valley start-ups offering free education through MOOCs, massive open online courses, the ivory towers of academia have been shaken to their foundations. University...

    7. (sports) Of a tournament or competition, allowing anyone to enter, especially or originally irrespective of professional or amateur status.

    8. (sports and games) Characterised by free-flowing play.

      • Compared to their last match, which was a dour and defensive affair, this was a very open game.
  4. Not completed or finalised.
    • an open question
    • to keep an offer or opportunity open

    1. Not settled; not decided or determined; not withdrawn from consideration.

    2. (sometimes business) Not fulfilled or resolved; incomplete.

      • I've got open orders for as many containers of red durum as you can get me.

    3. Not having one end joined to the other; not forming a closed loop.

      • an open curve, an open circuit

    4. (electricity, of a switch or circuit breaker) In a position such that a circuit is not completed, preventing electricity from flowing.

    5. (graph theory, of a walk) Having different first and last vertices.

    6. (phonetics, of a syllable) Ending in a vowel; not having a coda.

  5. Having a free variable.
  6. Which is part of a predefined collection of subsets of X, that defines a topological space on X.
  7. Of a note, played without pressing the string against the fingerboard.
  8. Of a note, played without closing any finger-hole, key or valve.
  9. Uttered with a relatively wide opening of the articulating organs; said of vowels.
    • "Supposing somebody sees you, with all those flowers too? Supposing somebody writes him a letter? Ooooh!" (a pure round open Tamil O.) - 1959, Anthony Burgess, Beds in the East (The Malayan Trilogy), published 1972,...
  10. Uttered, as a consonant, with the oral passage simply narrowed without closure.
  11. Source code of a computer program that is not within the text of a macro being generated.
  12. Having component words separated by spaces, as opposed to being joined together or hyphenated; for example, time slot as opposed to timeslot or time-slot.

Origin

Adjective from Middle English open, from Old English open (“open”), from Proto-West Germanic *opan, from Proto-Germanic *upanaz (“open”), from Proto-Indo-European *upo (“up from under, over”). Cognates * Scots apen (“open”) * Saterland Frisian eepen (“open”) * West Frisian iepen (“open”) * Cimbrian offe (“open”) * Dutch open (“open”) * German offen (“open”) * Vilamovian ufa, uffa (“open”) * Yiddish אָפֿן (ofn, “open”) * Danish åben (“open”) * Icelandic opinn (“open”) * Norwegian Bokmål åpen (“open”) * Norwegian Nynorsk open (“open”) * Swedish öppen (“open”) Compare also Latin supinus (“on one's back, supine”), Albanian hap (“to open”). Related to up. Verb from Middle English openen, from Old English openian (“to open”), from Proto-West Germanic *opanōn, from Proto-Germanic *upanōną (“to raise; lift; open”), from Proto-Germanic *upanaz (“open”, adjective). Cognate with Saterland Frisian...

Forms

more open opener most open openest

Synonyms

accessible unimpeded free

Antonyms

closed shut without prejudice checked closed-source proprietary

Hyponyms

half-open open-air open-and-shut open-armed open-arse open-collar open-door open-ended open-eyed open-face open-faced openhanded open-handed open-hearted open-hearth open-kneed open-mouthed open-plan open-work

Derived

at church every time the doors are open at church every time the doors swing open blow wide open break open byway open to all traffic clopen crack open distinguished open set double open jaw drop open fail open fauxpen get open half-open file half-open interval have someone's nose wide open home open in church every time the doors are open in open court in open store keep an eye open keep a weather eye open keep one's ears open keep one's eyes open

Noun

  1. Open or unobstructed space; an exposed location.
    • I can't believe you left the lawnmower out in the open when you knew it was going to rain this afternoon!
    • Wary of hunters, the fleeing deer kept well out of the open, dodging instead from thicket to thicket.
  2. Public knowledge or scrutiny; full view.
    • We have got to bring this company's corrupt business practices into the open.
  3. A defect in an electrical circuit preventing current from flowing.
    • The electrician found the open in the circuit after a few minutes of testing.
  4. A sports event in which anybody can compete, especially or originally irrespective of amateur or professional status.
    • the Australian Open
  5. The act of something being opened, such as an e-mail message.
    • The total number of opens from original, or unique, subscribers. - 2016, Ian Dodson, The Art of Digital Marketing, page 144:

Forms

opens

Derived

cold open in the open

Verb

  1. To make or become physically unobstructed, uncovered, etc.
    • Turn the doorknob to open the door.
    • The door opened all by itself.
    • I made a speaking trumpet of my hands and commenced to whoop “Ahoy!” and “Hello!” at the top of my lungs. […] The Colonel woke up, and, after asking what in brimstone was the matter, opened his mouth and roared “Hi!”...

    1. (transitive, intransitive) To make or become accessible or clear for passage by moving from a shut position.

    2. (transitive, intransitive) To make or become clear by removal of objects and obstructions, so as to allow passage, access, or visibility.

      • The icebreaker opened the channel.
      • The ice melted away and the channel opened.
      • He opened a path through the undergrowth.

    3. (transitive, intransitive) To unseal or uncover, or become unsealed or uncovered.

      • You can open your eyes now!
      • Her eyes opened wide.
      • He had kept on recording everything then, when he had been sure he was going to die, and he went on recording everything now, when he was suddenly consumed with hate for the boy in his arms and overwhelmed by a desire...

    4. (transitive, intransitive) To spread; to expand into a wider or looser position.

      • to open a closed fist
      • to open matted cotton by separating the fibres
      • to open a map, book, scroll, padlock

    5. (transitive, nursing) To make (a bed) ready for a patient by folding back the bedcovers.

      • Follow agency policy, or open the bed by folding the top linens back. - 2013, Susan C. deWit, Patricia A. Williams, Fundamental Concepts and Skills for Nursing, page 318:

    6. (transitive, intransitive, poker) To reveal one's hand.

      • Jeff opens his hand revealing a straight flush.

    7. (transitive, intransitive, engineering, gas and liquid flow, of valve or damper) To move to a position allowing fluid to flow.

    8. (especially sports, transitive, intransitive) To angle (a club, bat or other hitting implement) upwards and/or (for a right-hander) clockwise of straight.

  2. To cause or allow a gap to form or widen.
    • Mudchester Rovers opened a sizeable lead on their rivals.
    • A link opened under the strain, and the chain came apart.

    1. (transitive, intransitive, electricity, of a switch, fuse or circuit breaker) To move to a position preventing electricity from flowing.

  3. To make or become available for use or interaction.
    • He opened a secret bank account in Switzerland.
    • We're opening the phone lines in ten minutes.
    • Phone lines will open in ten minutes.

    1. (transitive, intransitive) To make or become operative or available.

    2. (transitive, intransitive) To make or become accessible to customers, clients or visitors.

      • I will open the shop an hour early tomorrow.
      • The summer fete was opened by the mayor.
      • The shop opens at 9:00.

    3. (transitive, intransitive) To make or become receptive or susceptible (to something).

      • Reading this book will open you to new ideas.
      • This policy will open the government to criticism.
      • As he grew older, he opened to new ways of doing things.

    4. (computing, transitive, intransitive) To connect to a resource (a file, document, etc.) for viewing or editing.

      • I can't open the file because someone else is editing it.

    5. (Manglish, Quebec) To turn on; to switch on.

      • Please open the lights, the (electric) fan, the TV.
  4. To start or begin.
    • The show was opened by a terrible Elvis impersonator.
    • Our band opened, and they came on second.
    • Vermont will open elk hunting season next week.

    1. (transitive or intransitive) To start (an event or activity) as the first performer or actor.

    2. (intransitive, with 'for') To precede another as a performer at a concert or show.

      • Our band opened for Nirvana.

    3. (intransitive) Of an event, activity etc., to start or get underway.

      • The meeting opened with a statement from the chairman.

    4. (transitive) To bring up, broach.

      • I don't want to open that subject.

    5. (transitive) To enter upon, begin.

      • to open a discussion
      • to open fire upon an enemy
      • to open trade, or correspondence

    6. (computing, transitive, intransitive) To start running (a program or application, especially one with a screen-based interface).

      • Click this icon to open Microsoft Word.

    7. (intransitive, cricket) To begin a side's innings as one of the first two batsmen.

    8. (intransitive, poker) To bet before any other player has in a particular betting round in a game of poker.

      • After the first two players fold, Julie opens for $5.
  5. To make an open relationship or marriage, i.e., with possible additional relationships.
    • He assured me, unequivocally, that he was, and that he rather enjoyed the side benefits of my trysts: I was happier and living more honestly, as well as off his back about many of the issues that had been troublesome...
    • I wouldn’t do it unless there is a reason for it, I wouldn’t open a marriage just for fun. I think it’s too dangerous. I know I’m a monogamous type of person—I like just one person at a time; actually sleeping with more...
    • Social situations involved in opening relationships are uncertain, rather than risky, environments. Although some people might say, “Absolutely not,” it may be difficult to predict the likelihood people will respond...
  6. To disclose; to reveal; to interpret; to explain.
    • The king opened himself to some of his council, that he was sorry for the earl's death. - 1622, Francis Bacon, The History of the Reign of King Henry the Seventh:
    • Unto thee have I opened my cause. - 1611, The Holy Bible, […] (King James Version), London: […] Robert Barker, […], →OCLC, Jeremiah 20:12:

Forms

opens opening opened no-table-tags glossary open openest openedst openeth -

Synonyms

unseal raise start bare

Antonyms

bare shut

Hyponyms

crack

Derived

a golden key can open any door eye-opener eye-opening misopen openability open a can of whoop ass open fire open its doors open one's big mouth open one's bowels open one's heart open one's legs open one's mind open one's mouth open out open Pandora's box open sesame open shop open someone's eyes open the attack open the ball open the batting open the door open the face