can't

• ca'n't (obsolete)

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

• (General Australian) enPR: känt, IPA^(key): /kaːnt/, [kʰä̃ːnt]

  • Audio (AU)

    (file)

• (Indian English) IPA^(key): /kaːɳʈ/
• (Received Pronunciation, some US speakers) enPR: känt, IPA^(key): /kɑːnt/, [kʰɑ̃ːnt]

  • Audio (UK)

    (file)

  • Rhymes: -ɑːnt
• (Scotland, Ireland, Northern England) enPR: känt
• (most US speakers, Canada, some Irish speakers) enPR: kănt, IPA^(key): /kænt/, [kæn(ʔ)]
  • (æ-tensing) IPA^(key): [kʰẽə̃nt], IPA^(key): [kʰɪ̃ə̃nt]

  • Audio (US)

    (file)

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

  • Audio (Southern US)

    (file)

  • Rhymes: -eɪnt
• 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 962368035, 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 837728611, 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; […]

• 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.

• 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