Main Entry: ¹can

Pronunciation: \kən, ˈkan also ˈken; dial ˈkin\

Function: verb

Inflected Form(s): past could \kəd, ˈku̇d\; present singular & plural can

Etymology: Middle English (1st & 3d singular present indicative), from Old English; akin to Old High German kan (1st & 3d singular present indicative) know, am able, Old English cnāwan to know — more at know

Date: before 12th century

transitive verb 1 obsolete : know, understand
2 archaic : to be able to do, make, or accomplishintransitive verb archaic : to have knowledge or skillverbal auxiliary 1 a : know how to <she can read> b : be physically or mentally able to <he can lift 200 pounds> c —used to indicate possibility <do you think he can still be alive> <those things can happen> ; sometimes used interchangeably with may d : be permitted by conscience or feeling to <can hardly blame her> e : be made possible or probable by circumstances to <he can hardly have meant that> f : be inherently able or designed to <everything that money can buy> g : be logically or axiologically able to <2 + 2 can also be written 3 + 1> h : be enabled by law, agreement, or custom to
2 : have permission to —used interchangeably with may <you can go now if you like>

usage Can and may are most frequently interchangeable in senses denoting possibility; because the possibility of one's doing something may depend on another's acquiescence, they have also become interchangeable in the sense denoting permission. The use of can to ask or grant permission has been common since the 19th century and is well established, although some commentators 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.