open
Americanadjective
-
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.
-
not yet balanced or adjusted, as an account.
-
not constipated, as the bowels.
-
Phonetics.
-
Linguistics. (of a class of items) readily admitting new members, as the class of nouns, verbs, or adjectives (opposed to closed).
-
Printing.
-
(of type) in outline form.
-
widely spaced or leaded, as printed matter.
-
-
Music.
-
(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.
-
-
Mathematics.
-
(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.
verb (used with object)
-
opens,
present (3rd person singular)
-
opened,
past participle, past
-
opening
present participle
-
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 byup ).
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.
-
Law.
-
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 byout ).
verb (used without object)
-
opens,
present (3rd person singular)
-
opened,
past participle, past
-
opening
present participle
-
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.
noun
-
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 open,
-
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.
-
verb phrase
adjective
-
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
-
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
-
music
-
(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
-
-
commerce
-
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
-
sport
-
(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
-
phonetics
-
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
verb
-
to move or cause to move from a closed or fastened position
to open a window
-
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
-
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
noun
-
any wide or unobstructed space or expanse, esp of land or water
-
See open air
-
sport a competition which anyone may enter
-
to make evident or public
-
to become) evident or public
Synonym Usage
See frank 1.
Other Word Forms
Derived Forms
-
opennessnoun
-
preopenverb (used with object)
-
half-openedadjective
-
openableadjective
-
self-openedadjective
-
semiopenadjective
-
unopenedadjective
-
openlyadverb
-
semiopenlyadverb
Inflected Forms
Participles
Conjugated Forms
Present
-
opensimple
-
openssimple
-
have openedperfect
-
has openedperfect
-
am openingprogressive
-
are openingprogressive
-
is openingprogressive
-
have been openingperfect progressive
-
has been openingperfect progressive
Past
-
openedsimple
-
had openedperfect
-
was openingprogressive
-
were openingprogressive
-
had been openingperfect progressive
Future
Etymology
Origin of open
First recorded before 900; (adjective) Middle English, Old English; cognate with Old Saxon opan ( Dutch open ), Old High German offan ( German offen ), Old Norse opinn, akin to up; (verb) Middle English openen, Old English openian; cognate with Old Saxon opanon ( Dutch openen ), Old High German offanōn ( German öffnen )
Explanation
Something that's open allows you to move or see through it, like an open window or an open gate. The adjective open describes something that's not closed or blocked up, like open curtains that provide a view of the garden outside. Open can also refer to something that's unfastened or parted — an open jar of peanut butter, an open eye, or an open book. Things that are vulnerable, straightforward, or uncovered are also open, and if you are open to suggestions, it means you are willing to consider new ideas.
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
Whether the vagueness of the rules are by design to leave it open to transgender women or a sign of an oversight that genuinely needs tightening up is not clear.
From BBC ● Aug. 10, 2026
"Our goal should be for American open source models to be the best globally. This requires removing the hurdles that make it harder for American open source models to compete," he said.
From Barron's ● Aug. 10, 2026
Meta CEO Mark Zuckerberg continued his AI PR campaign on Monday with a 6,500-word essay promising open models and a fund to invest in the communities where Meta hosts data centers.
From The Wall Street Journal ● Aug. 10, 2026
“Errors will always be part of soccer because there are many issues open to interpretation, and that’s what the referee is there for — to interpret them.”
From Los Angeles Times ● Aug. 10, 2026
He pulled the handle to open the door for her and she climbed in.
From "Legendary Frybread Drive-In" by Cynthia Leitich Smith
Rapper Dave, who has numerous Brit Awards, Ivor Novellos and a Mercury Prize to his name, opens up Kamal's track, The People That Saved Me, with poignant lyrics about love and memories.
From BBC ● Aug. 10, 2026
The chicken brand opens a restaurant every 3.5 hours somewhere in the world on average.
From The Wall Street Journal ● Aug. 9, 2026
In a moment when no one can quite agree on how to properly address what’s so clearly happening before our eyes with Grande, a film like “Maddie’s Secret” opens a dialogue.
From Salon ● Aug. 8, 2026
"These quantum states carry information. Our crystal can distinguish them and move them from one point to another in a robust way without requiring cryogenic cooling. That's what opens the door to practical quantum technologies."
From Science Daily ● Aug. 8, 2026
Once everyone is present, Tūtū opens us with a pule, prayer.
From "Clairboyance" by Kristiana Kahakauwila
Pope would be one option to replace Gay from within the squad, while Lawrence had a failed stint as a Test opener and Cox has opened in first-class cricket.
From BBC ● Aug. 10, 2026
Shaken of its favorite, the Tour opened up.
From The Wall Street Journal ● Aug. 10, 2026
Barton only opened official accounts after the tournament — and, according to him, not out of personal interest.
From Los Angeles Times ● Aug. 10, 2026
But he does not say who opened fire on Shakur.
From Barron's ● Aug. 10, 2026
That was what I was thinking of, as I opened the barn door.
From "An Elephant in the Garden" by Michael Morpurgo
Quentin Tarantino told Variety he had a production designer track one down for an opening shot of “Once Upon a Time... in Hollywood” at the Chinese Theatre before he rewrote the script.
From Los Angeles Times ● Aug. 10, 2026
The two sides meet at Hill Dickinson Stadium on Saturday, 22 August, on the opening weekend of the Premier League campaign.
From BBC ● Aug. 10, 2026
This translates to closing some of its underperforming pet-speciality locations and lowering store opening targets.
From The Wall Street Journal ● Aug. 10, 2026
The album opens with one of the best opening tracks of any debut album: “Blitzkrieg Bop.”
From Salon ● Aug. 10, 2026
Then she bent over the rock to look up into the opening in the cliff face, as though hoping to find an answer there.
From "Rowan of Rin" by Emily Rodda
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
