ˈwȯ(ə)rn, ˈwȯ(ə)n verb
( -ed/-ing/-s )
Etymology: Middle English warnen, from Old English warnian to take heed, warn; akin to Old High German warnōn to take heed, Old English wær aware, wary — more at wary
transitive verb
1.
a. : to put on guard : give notice, information, or intimation to beforehand especially of approaching or probable danger or evil
by … the display of a red lamp they managed to warn the driver — O.S.Nock
warned them about the quicksand
— sometimes used with off
young folks are warned off — Theodore Dreiser
b. : admonish , reprehend , counsel
warned me not to be too eager — London Calling
against such idiocy we are warned by an adage — W.F.Hambly
c. : to notify or apprise especially in advance : call to one's attention : make aware : inform
must warn you that they're only my opinions — Richard Joseph
the mounting heat of June warned us that the exposition would close its doors — Agnes Repplier
2. : to notify, summon, or dismiss by authority : bid to go or leave : command
a corporal called … to warn him for Driving School immediately — Earle Birney
heroes … warned so imperiously out of her modern living room — Virginia Woolf
3. : to prohibit from advancing, trespassing, or remaining by a warning gesture, notice, order, or device
lighthouses were built to warn sailors off the rocky … coast — American Guide Series: Oregon
warned away an English vessel — D.E.Clark
had been in the garden but an armed Partisan appeared and warned her inside — Milton Bracker
4. : to relate or report as a warning, intimation, caution, or admonishment
the commission could only warn that chaos and war would result — R.C.Pollock
intransitive verb
1. : to give a warning
their titles … warn of a meaning which goes behind story, people, even setting — E.K.Brown
he warns against … a fatal illusion — A.L.Locke
2. dialect Britain , of a clock : to strike a specified hour or to make sounds preparatory to striking
Synonyms:
caution , forewarn : warn is a general term lacking specific connotation and varying in meaning from simple appraisal of something, with or without any possible dangers, to truculent threats of personal violence
the introductory music warns us that another enjoyable evening of television is about to commence — advt
I warn him that the sword I wear shall pink his lily-scented cassock through and through, next time I catch him underneath your eaves — Robert Browning
caution may suggest a more formal, mild, well-meaning admonition, especially against imprudence, carelessness, or folly
cautions his readers against the common error of looking to antiquity for knowledge — H.T.Buckle
forewarn is likely to be used in more specific situations and to imply warning of coming danger given in time to permit prudent defense and safeguarding
very likely the parson had reason for being mad … there was a suggestiveness in the names of the acts which would have forewarned anybody — Margaret Deland