Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “open”


adjective uk   /ˈəʊ.pən/ us    /ˈoʊ-/

open adjective (NOT CLOSED)

A2 not closed or fastened: an open door/window An open suitcase lay on her bed. You left the packet open. Someone had left the window wide (= completely) open. He had several nasty open wounds (= those which had not begun to heal).

open adjective (READY)

A1 [after verb] ready to be used or ready to provide a service: The supermarket is open till 8.00 p.m. The road is open now, but it is often blocked by snow in the winter. The new hospital was declared open by the mayor.

open adjective (NOT ENCLOSED)

B1 not closed in or covered: From the garden there was a marvellous view over open countryside. It's not a good idea to camp in the middle of an open field (= one which is not covered with trees, bushes, etc.). The survivors were adrift on the open sea (= far from land).

open adjective (COMPUTER)

If a computer document or program is open, it is ready to be read or used: Make sure the file you're copying to is open before you click 'Paste'.

open adjective (AVAILABLE)

C1 [after verb] available; not limited: There are still several possibilities open to you. The competition is open to anyone over the age of 16. Is the library open to the general public? Their whole attitude to these negotiations is open to criticism (= can be criticized). I'd like to think I'm open to (= willing to consider) any reasonable suggestion. An accident would lay the whole issue of safety open (= cause it to be considered).

open adjective (NOT SECRET)

C2 not secret: There has been open hostility between them ever since they had that argument last summer. C2 honest and not trying to keep things secret: He's quite open about his weaknesses. I wish you'd be more open with me, and tell me what you're feeling. She has an honest, open face.

open adjective (NOT DECIDED)

not decided or certain: We don't have to make a firm decision yet. Let's leave it open. We can leave our offer open for another week, but we must have your decision by then. I want to keep my options open, so I'm not committing myself yet.


verb uk   /ˈəʊ.pən/ us    /ˈoʊ-/

open verb (BEGIN)

B2 [I or T] to (cause to) begin: I would like to open my talk by giving a brief background to the subject. I'm going to open an account with another bank. The Olympic Games open tomorrow. A new radio station is due to open (up) next month. The film opens (= will be shown for the first time) in New York and Los Angeles next week.

open verb (NOT CLOSED)

A1 [I or T] to move something to a position that is not closed, or to make something change to a position that is not closed: Could you open the window, please? You can open your eyes now - here's your present. The flowers open (out) in the morning but close again in the afternoon. From the kitchen there is a door that opens (out) into/onto the garden.informal "Open up (= open the door) - it's the police!" shouted the police officer, banging on the door. A2 [T] to remove or separate part of a container or parcel so that you can see or use what it contains: Don't open a new bottle just for me. I couldn't wait to open the letter.

open verb (READY)

A2 [I or T] If a shop or office opens at a particular time of day, it starts to do business at that time: The café opens at ten o'clock. He opens (up) his café at ten o'clock. B2 [T] If someone, usually someone important, opens a building, event, etc., they officially say that it is ready to be used or to start operating: The new hospital will be officially opened by the mayor on Tuesday.

open verb (AVAILABLE)

[T] to make something available: This research opens (up) the possibility of being able to find a cure for the disease. The country is planning to open (up) its economy to foreign investment.

open verb (COMPUTER)

B1 [T] If you open a computer document or program, you make it ready to read or use: To open a new document, click 'File', then click 'New'. Click the desktop icon to open the Cambridge Advanced Learner's Dictionary.


noun [S] uk   /ˈəʊ.pən/ us    /ˈoʊ-/

open noun [S] (NOT ENCLOSED)

the open somewhere outside, rather than in a building: It's good to be (out) in the open after being cooped up in an office all day.

open noun [S] (NOT SECRET)

bring sth out into the open to tell people information that was secret: It's time this issue was brought out into the open.
(Definition of open from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of open?
Browse related topics

You are looking at an entry to do with Uncertainty, but you might be interested in these topics from the Chance and possibility topic area:

Add Cambridge dictionaries to your browser to your website

Definitions of “open” in other dictionaries

Word of the Day


a girl or young woman

Word of the Day

Countability – grammar codes

by Dom Glennon​​,
November 26, 2014
Advices and informations Have you ever noticed strange codes in square brackets on entries in Cambridge Dictionaries Online and wondered what they mean? These are grammar codes, giving you a brief summary of how that word behaves grammatically. More information can be obtained by hovering your cursor over the code, and there’s

Read More 

ped-text verb

November 24, 2014
to text someone while walking I’m ped-texting, I’m looking down at my phone, 75 percent of the time.

Read More