Define can. can synonyms, can pronunciation, can translation, English dictionary definition of can. to be able to, have the power or skill to: I can take a bus to the airport. The word can is a versatile modal verb in English, commonly used to express ability, permission, possibility, and requests. Its meaning depends on the context, but understanding how to use it effectively will enhance your communication skills. The use of can to ask or grant permission has been common since the 19th century and is well established, although some feel may is more appropriate in formal contexts. May is relatively rare in negative constructions (mayn't is not common); cannot and can't are usual in such contexts. Can is usually used in standard spoken English when asking for permission. It is acceptable in most forms of written English, although in very formal writing, such as official instructions, may is often used instead: Persons under 14 unaccompanied by an adult may not enter. CAN definition: to be able to; have the ability, power, or skill to. See examples of can used in a sentence. Canva is a free-to-use online graphic design tool. Use it to create social media posts, presentations, posters, videos, logos and more. Learning to use can naturally in everyday sentences is one of the quickest ways to sound more confident in English. You will hear it when people talk about ability, ask for help, give permission, or make polite requests at work, in shops, and with friends. Here we will practice the most common.