silly

adjective sil·ly \ˈsi-lē\

: having or showing a lack of thought, understanding, or good judgment : foolish or stupid

: not practical or sensible

: not serious, meaningful, or important

sil·li·ersil·li·est

Full Definition of SILLY

archaic : helpless, weak

a : rustic, plain

b obsolete : lowly in station : humble

a : weak in intellect : foolish

b : exhibiting or indicative of a lack of common sense or sound judgment <a very silly mistake>

c : trifling, frivolous

: being stunned or dazed <scared silly> <knocked me silly>

— sil·li·ly \ˈsi-lə-lē\ adverb

— sil·li·ness \ˈsi-lē-nəs\ noun

— silly noun or adverb

See silly defined for English-language learners

See silly defined for kids

Origin of SILLY

Middle English sely, silly happy, innocent, pitiable, feeble, from Old English sǣlig, from sǣl happiness; akin to Old High German sālig happy

First Known Use: 14th century

Related to SILLY

Synonyms: birdbrained, ditzy (or ditsy), dizzy, featherbrained, flighty, frivolous, frothy, futile, goofy, harebrained, light-headed, light-minded, puerile, scatterbrained, giddy, yeasty

Antonyms: earnest, serious, serious-minded, sober, unfrivolous

Synonym Discussion of SILLY

simple, foolish, silly, fatuous, asinine mean actually or apparently deficient in intelligence. simple implies a degree of intelligence inadequate to cope with anything complex or involving mental effort <considered people simple who had trouble with computers>. foolish implies the character of being or seeming unable to use judgment, discretion, or good sense <foolish stunts>. silly suggests failure to act as a rational being especially by ridiculous behavior <the silly antics of revelers>. fatuous implies foolishness, inanity, and disregard of reality <fatuous conspiracy theories>. asinine suggests utter and contemptible failure to use normal rationality or perception <an asinine plot>.