(noun, adjective, verb)


1. affording unobstructed entrance and exit; not shut or closed

- an open door

- they left the door open

Similar word(s): ajar, open, unfastened

2. affording free passage or access

- open drains

- the road is open to traffic

- open ranks

Similar word(s): open, unfastened, opened, unstoppered, yawning, unsealed

3. with no protection or shield

- open to the weather

- an open wound

Similar word(s): unprotected, exposed

4. open to or in view of all

- an open protest

- an open letter to the editor

Similar word(s): public

5. used of mouth or eyes

- keep your eyes open

- his mouth slightly opened

Similar word(s): agape, gaping, agaze, staring, wide, yawning, opened

6. not having been filled

- the job is still open

Similar word(s): available

7. accessible to all

- open season

- an open economy

Similar word(s): unrestricted

8. not defended or capable of being defended

- an open city

- open to attack

Similar word(s): vulnerable, assailable, undefendable, undefended

9. (of textures) full of small openings or gaps

- an open texture

Similar word(s): coarse, harsh, loose

10. having no protecting cover or enclosure

- an open boat

- an open fire

- open sports cars

Similar word(s): unenclosed

11. (set theory) of an interval that contains neither of its endpoints

12. not brought to a conclusion; subject to further thought

- an open question

Similar word(s): unsettled, undecided, undetermined, unresolved

13. not sealed or having been unsealed

- the letter was already open

- the opened package lay on the table

Similar word(s): unsealed, opened

14. without undue constriction as from e.g. tenseness or inhibition

- the clarity and resonance of an open tone

- her natural and open response

Similar word(s): unconstricted

15. ready or willing to receive favorably

Similar word(s): acceptant, acceptive, admissive, assimilative, hospitable, receptive

16. open and observable; not secret or hidden

- open ballots

Similar word(s): explicit, expressed, bald, barefaced, naked, raw, undisguised, visible, public, unconcealed, overt

17. possibly accepting or permitting

- open to interpretation

- an issue open to question

Similar word(s): susceptible, capable, subject

18. affording free passage or view

- open waters

- the open countryside

Similar word(s): unobstructed, clear

19. (of a person) openly straightforward and direct without secretiveness.

- an open and trusting nature

Similar word(s): artless, ingenuous, candid

20. ready for business

- the stores are open

Similar word(s): active

Sentences with open as an adjective:

- Turn left after the second open door.

- It was as if his body had gone to sleep standing up and with his eyes open.

- an open hand; an open flower; an open prospect

- Banks are not open on bank holidays.

- I am open to new ideas.

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

- The man is an open book.

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

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

- to keep an offer or opportunity open


1. a clear or unobstructed space or expanse of land or water

- finally broke out of the forest into the open

Similar word(s): clear

Definition categories: location, area, country

2. where the air is unconfined

- the concert was held in the open air

- camping in the open

Similar word(s): outdoors

Definition categories: location, exterior, outside

3. a tournament in which both professionals and amateurs may play

Definition categories: event, tournament, tourney

4. information that has become public

- all the reports were out in the open

Similar word(s): surface

Definition categories: thought

Sentences with open as a noun:

- The electrician found the open in the circuit after a few minutes of testing.

- 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.

- We have got to bring this company's corrupt business practices into the open.


1. cause to open or to become open

- Mary opened the car door

Definition categories: contact

2. start to operate or function or cause to start operating or functioning

- open a business

Definition categories: social

3. become open

- The door opened

Definition categories: contact, turn

4. begin or set in action, of meetings, speeches, recitals, etc.

- He opened the meeting with a long speech

Definition categories: social, commence, start

5. spread out or open from a closed or folded state

- open the map

Similar word(s): spread, unfold

Definition categories: contact, undo

6. make available

- This opens up new possibilities

Definition categories: change, afford, give, yield

7. become available

- an opportunity opened up

Definition categories: change, arise

8. have an opening or passage or outlet

- The bedrooms open into the hall

Definition categories: stative

9. make the opening move

- Kasparov opened with a standard opening

Definition categories: competition, go, move

10. afford access to

- the door opens to the patio

Similar word(s): afford, give

Definition categories: possession

11. display the contents of a file or start an application as on a computer

Definition categories: perception, display, exhibit, expose

Sentences with open as a verb:

- Turn the doorknob to open the door.

- He opened a path through the undergrowth.

- I don't want to open that subject.

- I will open the shop an hour early tomorrow.

- Vermont will open elk hunting season next week.

- The door opened all by itself.

- The shop opens at 9:00.

- to open a discussion; to open fire upon an enemy; to open trade, or correspondence; to open a case in court, or a meeting

- After the first two players fold, Julie opens for $5.

- Jeff opens his hand revealing a straight flush.

- to open a closed fist

- to open matted cotton by separating the fibres