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adjective sil·ly \ˈsi-lē\

Simple Definition of silly

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

  • : not practical or sensible

  • : not serious, meaningful, or important

Source: Merriam-Webster's Learner's Dictionary

Full Definition of silly


  1. 1 archaic :  helpless, weak

  2. 2a :  rustic, plainb obsolete :  lowly in station :  humble

  3. 3a :  weak in intellect :  foolishb :  exhibiting or indicative of a lack of common sense or sound judgment <a very silly mistake>c :  trifling, frivolous

  4. 4 :  being stunned or dazed <scared silly> <knocked me silly>

sillily play \ˈsi-lə-lē\ adverb
silliness play \ˈsi-lē-nəs\ noun
silly noun or adverb

Examples of silly in a sentence

  1. I hope I didn't make any silly mistakes.

  2. The idea does seem a bit silly.

  3. That's the silliest thing I've ever heard.

  4. You drove in this weather? What a silly thing to do!

  5. Silly me. I locked myself out of the car again.

  6. Ask a silly question, and you get a silly answer.

  7. I can't ask you to do that. Don't be silly. It is my pleasure.

  8. What a silly little purse. It looks too small to hold everything that I'd need to carry.

  9. I'm tired of watching silly movies.

  10. The book was a silly waste of time.

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

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>.

Rhymes with silly

SILLY Defined for Kids


adjective sil·ly \ˈsi-lē\

Definition of silly for Students


  1. 1 :  having or showing a lack of common sense :  foolish <Silly me! I forgot again.> <What a silly mistake!>

  2. 2 :  not serious or important <a silly reason>

  3. 3 :  playful and lighthearted <silly jokes>

silliness noun

Seen and Heard

What made you want to look up silly? Please tell us where you read or heard it (including the quote, if possible).


a division or portion of a pool or whole

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