Did you know?

Click any word in a definition or example to find the entry for that word

or - definition and synonyms


What are red words?

90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.



The thesaurus of synonyms and related words is fully integrated into the dictionary. Click on the thesaurus category heading under the button in an entry to see the synonyms and related words for that meaning.

conjunction or pronunciation in American English /ɔr/
  • Facebook
  • Twitter
  1. 1
    used for connecting possibilities or choices. In a list, “or” is usually used only before the last possibility or choice

    Which color do you want – red, green, yellow, or blue?

    He’s probably at lunch or in a meeting.

    either... or:

    “When will you get the results?” “Either tomorrow or the day after.”

    whether... or:

    You don’t care whether he lives or dies, do you?

    or not:

    The jury must decide whether the prisoner is guilty or not.

    Synonyms and related words
  2. 2
    used for including someone or something else in a negative statement

    She’s had nothing to eat or drink all day.

    I never had any help or advice from my parents.

    Synonyms and related words
  3. 3
    used between two similar numbers for showing that you do not know what the exact number is
    one or two/two or three/three or four etc.:

    I can photocopy your notes. It’ll only take a minute or two.

    The car has to be serviced every five or six thousand miles.

    Synonyms and related words
  4. 4
    used for saying what will happen if someone does not do something

    The soldiers told everyone to leave or they would be shot.

    or else:

    We must deal with the problem now, or else it will be too late.

    You’d better do what I say, or else (=I will do something bad to you).

    Synonyms and related words
  5. 5
    used for introducing a comment that corrects or adds more information to what you have just said

    There are six cash machines, or ATMs, in the main airport terminal.

    or rather:

    This is a problem for the government, or rather for a federal agency, to deal with.

    Synonyms and related words
  6. 6
    used when you are trying to show that something must be true, by saying that the situation would be different if it was not true

    The candidate obviously hasn’t chosen a running mate or he would have made the announcement.

    or else:

    It must be something serious, or else they wouldn’t have radioed for help.

    Synonyms and related words

Open Dictionary


the activity of exploring abandoned buildings and other manmade structures

add a word


A must for anyone with an interest in the changing face of language. The Macmillan Dictionary blog explores English as it is spoken around the world today.

global English and language change from our blog
Macmillan learn live love play