Did you know?

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

sign up - 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.

phrasal verb
Word Forms
present tense
I/you/we/theysign up
he/she/itsigns up
present participlesigning up
past tensesigned up
past participlesigned up

Related words

  1. 1
    [intransitive] to agree to do something, or to join a course or organization
    sign up for:

    She’s decided to sign up for evening classes.

  2. 2
    [transitive] to put someone’s name on an official list for something
    sign someone up (to do something):

    They’ve signed me up to do voluntary work next month.

  3. 3
    [transitive] same as sign2 (sense 2)

    We have signed up two new players.

See also main entry: sign

sea lion

in an online conversation, repeatedly asking a person questions which suggest that you are interested in what they are talking about, but are actually intended to annoy them

BuzzWord Article

Open Dictionary


an electric skateboard

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