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Synonyms

silly

American  
[sil-ee] / ˈsɪl i /

adjective

sillier, comparative silliest superlative
  1. weak-minded or lacking good sense; stupid or foolish.

    a silly writer.

    Synonyms:
    dull-witted, dull, dim, dense, brainless, senseless, witless
    Antonyms:
    sensible
  2. absurd; ridiculous; irrational.

    a silly idea.

    Synonyms:
    preposterous, nonsensical, asinine, inane
  3. humorous and playful in a clownish, whimsical, or exaggerated way; showing unrestrained high spirits.

    With a few April Fools’ Day tricks, students have a respite from seriousness and get to just be silly and laugh.

  4. stunned; dazed.

    He knocked me silly.

  5. Cricket. (of a fielder or the fielder's playing position) extremely close to the batsman's wicket.

    silly mid off.

  6. Archaic. rustic; plain; homely.

  7. Archaic. weak; helpless.

  8. Obsolete. lowly in rank or state; humble.


noun

sillies plural
  1. Informal. a silly or foolish person.

    Don't be such a silly.

silly British  
/ ˈsɪlɪ /

adjective

  1. lacking in good sense; absurd

  2. frivolous, trivial, or superficial

  3. feeble-minded

  4. dazed, as from a blow

  5. obsolete homely or humble

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. (modifier) cricket (of a fielding position) near the batsman's wicket

    silly mid-on

  2. Also called: silly-billyinformal a foolish person

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

Where does silly come from? You have probably heard someone say that language is constantly changing. We are definitely guilty of saying that here at Dictionary.com. But what does that mean exactly? Well, the story of the word silly is one clear—and fascinating—illustration. Languages change in many ways. The sounds and forms of a language can morph. The underlying structures of a language can shift. New words are created. Old words die out. And as we see in the case of silly, the meaning of words can develop in some remarkable ways. Today, we generally use the word silly to describe something as “foolish.” Something silly can be amusing, as when kids make silly faces or play silly games. Something silly can also be, more dismissively, stupid. For example: The politician’s promises were nothing but silly pipedreams.  But care to guess what the original sense of silly was? “Blessed.” We’re not being silly. Among the oldest recorded senses of silly—or, more accurately, the word that became our modern word silly—was “spiritually blessed.” Those senses are recorded in the early 1200s. So how did we get to “foolish”?Dig deeperSilly ultimately comes from the Old English (c. 450–c1150) word gesǣlig, meaning “happy, blessed.” Talk about language change! Let’s break this gesǣlig down. That ge- is an Old English prefix that was effectively lost. That -ig became -y, which is all over English today, as in juicy or dreamy. And sǣl meant “happiness.”During Middle English (c1150–1475), this gesǣlig developed into new forms (see our entry at the archaic word seely) and many new senses. The word acquired the senses of “holy, innocent, helpless,” then “pitiable” and “insignificant,” then “simple” and “ignorant.” By the mid- to late 1500s, silly had gained the meaning of “lacking good sense, foolish, irrational, ridiculous.”It’s hard to say why, exactly, but there may be something of a through-line in the incredible sense development of silly. Something “happy” can be considered “favored by God.” Something “favored by God” can be considered “holy,” and so “innocent,” which may be said of a small animal or child who is “harmless” or “defenseless.” (Are you following us so far?) And if you can’t protect yourself or you lack power, you might be considered “worthless” or “miserable”—and so silly apparently jumps to “foolish.”

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Adjectives

Etymology

Origin of silly

First recorded in 1375–1425; earlier sylie, sillie “foolish, feeble-minded, simple, pitiful”; late Middle English syly, variant of sely seely

Explanation

Silly describes something that can't be taken seriously. You might not mind telling silly jokes, but you don't want to be told a project you've worked hard at is silly. Silly originally meant “happy,” which gives the sense of children's games or harmless jokes. Later, it came to mean “foolish”: silly ideas are looked down on because they're not very smart. Silly can also mean a state of foolishness brought on in a specific way. Your mother “worried herself silly” when you stayed out late, and promised to “slap you silly” when you got home.

Keep Reading on Vocabulary.com

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Not that it was foolproof, but it was just such a silly idea and I was a fan of David Wain and those guys anyway.

From Los Angeles Times Jul. 6, 2026

It was a silly idea because of the way it would have impacted the thousands of fans flying in from all over the world to watch it.

From BBC Jul. 4, 2026

The reason this distinction matters is that bull markets usually end because of broad excess and tightening liquidity — not because a few flashy IPOs come public at silly valuations.

From MarketWatch Jun. 25, 2026

“If you think about it, it’s completely silly to do it. But part of any military organization is taking a bunch of individuals and making them a team.”

From Slate Jun. 24, 2026

Mom’s smile would disappear and she’d complain that he was wasting money on silly, impossible games, and he’d tell her she was being a control freak and that “our smiles were worth the money.”

From "Red Flags and Butterflies" by Sheryl Azzam

The worst outcome I could imagine was a case of the sillies, sleepies, or munchies.

From Slate Jun. 13, 2026

Chilly weather brought out the sillies in our giant panda cub, who showed off his somersault style.

From Washington Post Feb. 7, 2023

Though once is enough for me, I promise not to find that any more offensive than those flag-decorated pubs full of World Cup sillies.

From The Guardian May 31, 2010

If you are the parent of a preschooler, suffice it to say that Raffi, in the throes of middle age, is shaking his sillies out.

From Time Magazine Archive

“Oh, you sillies, it’s just that the power is out. Your eyes still work fine.”

From "The Benefits of Being an Octopus" by Ann Braden

The Doctor will be sillier or more serious, calmer or crazier, more physical or more cerebral, and never again necessarily a white dude.

From Los Angeles Times Jun. 11, 2026

The awards, which celebrate the sillier side of science, have held raucous ceremonies that see the winners showered with paper aeroplanes at universities in Massachusetts since 1991.

From Barron's Mar. 10, 2026

Some of the sillier visualizations of heaven seem chosen to prove that filmmakers, no less than regular people, struggle to conceive its particulars.

From The Wall Street Journal Feb. 7, 2026

It’s all the sillier because—to risk taking the president’s goals at face value—there is a way to put lots of American men to work with their hands.

From Slate Apr. 14, 2025

I suppressed this impulse also, as it was even sillier than the first.

From "The Left Hand of Darkness" by Ursula K. Le Guin

“Salmon,” I ask this morning, “can you tell me in your silliest voice what you want in your lunch?”

From Slate May 10, 2026

"I took the silliest fall that ultimately resulted in me dislocating my shoulder," Kim said.

From Barron's Jan. 8, 2026

“He was not merely my grandfather; he was my best friend. Nothing brought me greater joy than making him laugh. He had the best laugh. And the silliest dance moves.”

From Los Angeles Times Feb. 25, 2025

She approached the subjects she covered with genuine empathy that previously seemed like it was missing from the show’s sometimes stuffy programming, where even the silliest segments felt rehearsed.

From Salon Jan. 10, 2025

I remember Mitch because he would ask the silliest questions, like, “Why can’t we see air?” and while everyone would snigger underneath their breath, she would answer his question.

From "Dumplin'" by Julie Murphy

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