# open

Pronunciation: say "OH-puhn" US /ˈoʊ.pən/, UK /ˈəʊ.pən/, AUS /ˈəʉ.pən/

## Verb

1. To move a door, lid, cover or seal so that something is no longer shut or sealed, or to become no longer shut, giving access or a way through.
   - Simple: To move something such as a door, lid or box so that it is not shut any more.
   - _Customs officers open suspicious parcels for inspection._
   - _The vacuum-sealed bag opens with a soft hiss._
2. To make or become ready and available to customers, visitors or users, whether for the day or for the first time.
   - Simple: To make or become ready for people to use or visit, for the day or for the first time.
   - _The company plans to open three new branches downtown._
   - _The restaurant opens for dinner only on weekends._
5. To begin, or to start an event, activity, meeting or discussion.
   - Simple: To start, or to make something such as a meeting or event start.
   - _The festival opens with a parade through the town center._
   - _Negotiations open next week in Geneva._
6. To load a file or document, or start a program or app, so that it can be viewed, edited or used.
   - Simple: To make a file or app start on a computer or phone so you can use it.
   - _Double-click the icon to open the spreadsheet._
   - _Large files open slowly on older machines._
12. To make or become clear by removing objects that block the way, allowing passage, access, or sight.
   - Simple: To take away things that block the way, so people can pass or see.
   - _Crews open the channel by dredging silt from the riverbed._
   - _The view opens dramatically as the trail crests the ridge._
15. To cause or allow a gap to form or widen, or to come apart so that a gap forms.
   - Simple: To make a gap appear or get bigger, or to come apart so a gap appears.
   - _The race leader opened a ten-second gap on the final climb._
   - _Seams can open under heavy loads if the stitching is weak._
24. To spread out or unfold, or to make something do so, as when a map is laid flat or a flower blooms.
   - Simple: To spread out wider, or to become looser.
   - _He opened the map across the table to plan the route._
   - _The flowers open as the morning slowly warms._
21. To begin an event or activity as the first performer or act.
   - Simple: To be the first to perform and so begin a show or event.
   - _Local acts open the concert before the headliner takes the stage._
   - _She opened for a famous comedian during last summer's tour._
25. To make someone or something receptive or susceptible to something, or to become so.
   - Simple: To make someone ready for new things or easy to attack, or to become ready for new things.
   - _Publishing the emails would open the senator to charges of hypocrisy._
   - _After a year of therapy, he slowly began to open to the possibility of forgiving his father._
27. To raise or introduce a subject for discussion.
   - Simple: To bring up a topic so people can start talking about it.
   - _He opened the matter of funding before anyone else could speak._
   - _I'd rather not open the subject of her divorce at the dinner table._
22. To establish a new account, file or case, most commonly an account with a bank.
   - Simple: To start a new account, file or case, most often a bank account.
   - _Customers can open a checking account online without visiting a branch._
   - _The agency opened a file on the contractor after the first complaint came in._

## Adjective

3. Not covered or sealed, with a gap or opening that shows what is inside.
   - Simple: Not closed or covered, so you can see or reach what is inside.
   - _The jar sat open on the counter, its lid resting beside it._
   - _Someone had left the bag of chips open, and now they're all stale._
4. Ready for business, or ready to admit customers, visitors or the public.
   - Simple: Ready for customers or visitors to come in.
   - _The gardens remain open to the public from dawn until dusk._
   - _The new gallery is open to anyone who books a slot in advance._
7. Free and available for use or operation.
   - Simple: Ready and free to be used.
   - _Registration is open, so applicants can sign up immediately._
   - _Three positions remain open in the research department._
8. Available to the public; not hidden or restricted from general view.
   - Simple: Able to be seen or used by everyone, and not kept secret.
   - _City budget records are open to anyone who files a request._
   - _The hearing was deliberately kept open so the community could observe._
9. Of a space, free of objects and things that block the way.
   - Simple: Having lots of empty room with nothing in the way.
   - _The cattle wandered freely across the open plain._
   - _Once the movers took out the furniture, the whole floor was open for dancing._
10. Willing to consider new ideas, suggestions, or experiences without resistance.
   - Simple: Ready to listen to new ideas and not against them.
   - _The director remained open to criticism throughout the rehearsals._
   - _Negotiators who stay open to compromise tend to reach a deal faster._
11. Made public and usable under a free license, with no proprietary components.
   - Simple: Shared with everyone under a license that lets anyone use, copy and change it, with no restricted parts.
   - _Because the file format is an open standard, any company can build software that reads it._
   - _The university publishes its lecture notes and videos as open courseware._
13. Of a person, not hiding their feelings or opinions; honest and candid.
   - Simple: Of a person, willing to share their true feelings and opinions.
   - _The new manager is remarkably open about the company's problems._
   - _Being open with strangers came naturally to her._
14. Unobstructed, so that something can pass through or along it.
   - Simple: Clear, so that things can move through or along it.
   - _Crews worked through the night to keep the mountain pass open._
   - _With the channel open, ships could finally reach the harbor._
16. Not yet settled, decided, or determined; still under consideration.
   - Simple: Still not decided or settled.
   - _The committee kept the proposal open pending further evidence._
   - _Whether the museum will expand is still an open question._
18. Of a tournament or competition, allowing anyone to enter, especially regardless of amateur or professional standing.
   - Simple: Letting any player enter a contest, whether paid or not.
   - _The golf event is open to anyone who clears the qualifying score._
   - _Because the tournament was open, club players got to face national champions._
20. Not concealed; done plainly for all to see.
   - Simple: Not hidden or secret, and done where everyone can see.
   - _The two leaders showed open contempt for each other during the debate._
   - _Her support for the cause was open and unmistakable._
23. Spread apart rather than drawn together, folded, or contracted.
   - Simple: Spread out wide, not folded up or pressed together.
   - _The peacock's tail stood fully open in a wide fan of feathers._
   - _He laid the newspaper open across the breakfast table._
26. Resulting from a cut, puncture or other break that leaves an internal part of the body no longer protected by the skin.
   - Simple: With the skin cut or broken, so that a part inside the body is no longer covered.
   - _The skier was flown to the hospital with an open fracture of the lower leg._
   - _An open wound on the hand can let bacteria into the bloodstream._
28. Of a program or application, especially one with an on-screen interface: running.
   - Simple: Running on a computer or phone, like an app you are using.
   - _Leaving dozens of apps open can slow down an older phone._
   - _The video editor stayed open in the background while he answered emails._
29. Liable to be affected by, or vulnerable to, the stated means.
   - Simple: Easy to affect or harm in the way that is named.
   - _Skipping the audit left the firm open to fraud._
   - _The unguarded flank left the army open to attack._
30. In team sports, of a player or goal: not guarded or marked by anyone on the opposing team.
   - Simple: In team sports, not guarded by a player from the other team.
   - _The quarterback spotted his tight end wide open in the end zone._
   - _With the goalie out of position, she had an open goal and calmly tapped the ball in._
31. Having ends that are not joined together; not forming a closed loop.
   - Simple: Having two ends that do not join into a ring.
   - _The bracelet was an open band that slipped over the wrist._
   - _A break in the wiring left the circuit open and the lamp dark._
33. Describing a relationship or marriage in which the partners agree that each may have romantic or sexual relationships with other people.
   - Simple: Used about a relationship or marriage in which both partners agree they can date or have sex with other people.
   - _After fifteen years of marriage, the couple decided to try an open marriage._
   - _Keeping an open relationship healthy, the therapist said, depends on rules both partners actually accept._

## Noun

17. An area of unobstructed, exposed space, away from shelter or cover.
   - Simple: A wide, empty space with nothing to hide behind.
   - _The soldiers were caught in the open as enemy troops fired from the ridge._
   - _Out in the open, the wind hit them with full force._
19. A sporting event in which anybody can compete, especially regardless of amateur or professional status.
   - Simple: A sports contest that anyone can enter, whether paid players or not.
   - _The tennis open drew a field of seasoned pros and rising amateurs._
   - _Qualifying rounds for the open ran all week before the main draw._
32. The state of being publicly known or subject to scrutiny; full view.
   - Simple: A state where everyone can see or know about something.
   - _Years of quiet dealings were dragged into the open by the inquiry._
   - _Bringing the dispute into the open forced both sides to explain themselves._

## Other meanings

- (adjective) Of a door, gate, or lock, not fastened, so it can be opened, though it is still shut.
- (adjective) Of a valve, tap, or similar control, set so that liquid or gas can pass through.
- (adjective) Of a sandwich or similar dish, made with one piece of bread and the filling left uncovered on top.
- (adjective) Of weather or a climate, mild enough that frost and snow do not close roads or rivers.
- (adjective) Of a file, network connection, or similar resource, currently being accessed or in use.
- (adjective) In law, of a settlement offer or letter, made on the record so that it can be shown to the court, unlike a confidential offer.
- (adjective) Freely available to anyone, as with open-access publishing, or following the practices of open science.
- (adjective) Of a game or match, flowing freely, with lots of attacking and space rather than tight, defensive play.
- (adjective) Of an electric circuit or switch, not forming a complete path, so that current cannot flow.
- (adjective) In graph theory, of a walk or path, starting at one vertex and finishing at a different one.
- (adjective) Of a syllable, finishing with a vowel sound and no consonant after it.
- (adjective) In logic, of a formula, having at least one occurrence of a variable not bound by any quantifier.
- (adjective) In topology, of a set, belonging to the chosen family of subsets that gives a space its topological structure.
- (adjective) Of a note on a stringed instrument, sounded on a string that no finger is holding down.
- (adjective) Of a note on a wind instrument, played without covering finger holes, closing keys, or using valves.
- (adjective) Of a vowel, pronounced with the tongue held low and the mouth wide, as in father.
- (adjective) Of a consonant, made by narrowing the mouth passage without shutting it completely, as with f or s.
- (adjective) In programming with macros, describing program text that lies outside the body of the macro being expanded.
- (adjective) Of a compound word, written as separate words with a space, like ice cream, rather than closed up or hyphenated.
- (adjective) Of the face of a golf club, cricket bat or racket, tilted upward or turned outward from straight, rightward for a right-handed player.
- (verb) In nursing, to fold the covers of a made bed back so a patient can get in.
- (verb) In card games, to lay down or show the cards one is holding.
- (verb) To shift into a setting that lets liquid or gas through, as a valve or tap does.
- (verb) To tilt the face of a golf club, cricket bat or racket upward, or turn it outward from straight, rightward for a right-handed player.
- (verb) Of a switch or circuit, to break the connection so that current stops.
- (verb) To switch a light, radio, or other device on.
- (verb) To be the warm-up act that plays before the headliner.
- (verb) In cricket, to be one of the pair of batters who start a team's innings.
- (verb) In poker, to make the first bet in a round of betting.
- (verb) To change a marriage or relationship so that the partners may also have other partners.
- (verb) To make something known, or to explain or interpret its meaning.
- (noun) A gap or broken connection in wiring that keeps electricity from getting through.
- (noun) A single occasion on which something, typically an email, is opened.

## Origin

The adjective comes from Middle English 'open', from Old English 'open', tracing back through Proto-West Germanic and Proto-Germanic *upanaz to a Proto-Indo-European root meaning 'up from under, over'. It has cognates like Dutch 'open', German 'offen', and Swedish 'öppen', and is related to the word 'up'. The verb derives similarly from Old English 'openian', and the noun comes from the verb, with the sports sense being a shortening of 'open competition'.

Source: DictionaryAI, https://dictionaryai.com/define/open (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).