can't

• ca'n't (obsolete)
• cain't (dialectal, Southern US)

can +‎ -n't, since 1706[1] or earlier.[2]

• (Received Pronunciation, Northern England, Wales, some US speakers) enPR: känt, IPA^(key): /kɑːnt/, [kʰɑ̃ːnt]

  • Audio (UK)

    (file)

  • Rhymes: -ɑːnt
• (General American, Canada, some Irish speakers) enPR: kănt, IPA^(key): /kænt/, [kʰæn(ʔ)]
  • (æ-tensing) IPA^(key): [kʰẽə̃nʔ ~ kʰɪ̃ə̃nʔ]

  • Audio (US)

    (file)

  • Rhymes: -ænt
    • (Southern American English) IPA^(key): [kʰẽɪ̃nt], [kʰẽɪ̃n(ʔ)]

      • Audio (Southern US)

        (file)

      • Rhymes: -eɪnt
• (General Australian, New Zealand) enPR: känt, IPA^(key): /kaːnt/, [kʰä̃ːnt], [kʰä̃ːnʔ]

  • Audio (AU)

    (file)

• (Indian English) IPA^(key): /kaːɳʈ/
• Homophones: cant, Kant (in some dialects)

can't

1. Cannot (negative auxiliary[3]); is unable to; does not have the ability to.

   Antonyms: be able to, can

   I can’t quite get it to work.

   • 2012, BioWare, Mass Effect 3 (Science Fiction), Redwood City: Electronic Arts, →OCLC, PC, scene: Tuchanka:

     Shepard: Mordin, walk away.
     Mordin: Can't do that, Shepard.
     Shepard: I don't have a choice here. Walk away, or I will fire.

2. Is forbidden to; is not permitted to.

   Antonyms: be able to, can, have to, must

   You can’t enter the hall without a ticket.

3. Often followed by be: is logically impossible.

   Antonyms: be able to, can, have to, must

   The butler can’t be the murderer because he was in London that evening.

   • 1750, W[illiam] Ellis, The Country Housewife's Family Companion: Or Profitable Directions for Whatever Relates to the Management and Good Œconomy of the Domestick Concerns of a Country Life, According to the Present Practice of the Country Gentleman's, the Yeoman's, the Farmer's, &c. Wives, in the Counties of Hertford, Bucks, and Other Parts of England: Shewing how Great Savings may be Made in Housekeeping: [...] With Variety of Curious Matters [...] The Whole Founded on Near Thirty Years Experience, London: Printed for James Hodges, at the Looking-glass, facing St. Magnus Church, London-Bridge; and B. Collins, bookseller, at Salisbury, →OCLC, page 157:

     To make Capons […] [S]ome for this Purpoſe make it their Buſineſs after Harveſt-time to go to Markets for buying up Chickens, and between Michaelmas and All-hollantide caponize the Cocks, when they have got large enough to have Stones [i.e., testes] of ſuch a Bigneſs that they may be pulled out; for if they are too little, it can't be done; […]

• Although may and can are synonyms, can’t and mayn’t (including their uncontracted forms) are not, except when used interrogatively. “You can’t have a console” means you must not have a console, but “you mayn’t have a console” means you are not guaranteed to have a console, with the implication that you still may if you do.
• Some US dialects that glottalize the final /t/ in can’t (/kæn(ʔ)/), in order to differentiate can’t from can, pronounce can as /kɛn/ even when stressed.

• couldn't, mayn't, mightn't, oughtn't, shan't, shouldn't, won't, wouldn't

• you can't say fairer than that

For other translations, see can and not.

• Appendix:English modal verbs
• Appendix:English tag questions

• NCTA, T-Can