fool

1 of 3

noun

ˈfül 

plural fools

1

: a person lacking in judgment or prudence

Only a fool would ride a motorcycle without wearing a helmet.

2

a

: a retainer (see retainer entry 1 sense 1) formerly kept in great households to provide casual entertainment and commonly dressed in motley with cap, bells, and bauble

b

: one who is victimized or made to appear foolish : dupe

History has made fools of many rash prophets.

3

a

: a person lacking in common powers of understanding or reason

b

: one with a marked propensity or fondness for something

a dancing fool

a fool for candy

4

: a cold dessert of pureed fruit mixed with whipped cream or custard

fool

2 of 3

adjective

: foolish, silly

barking its fool head off

fool

3 of 3

verb

fooled; fooling; fools

intransitive verb

1

a

: to behave foolishly

told the children to stop their fooling

see also fool around

b

: to meddle, tamper, or experiment especially thoughtlessly or ignorantly

Don't fool with that drill.

see also fool around with

2

a

: to play or improvise a comic role

b

: to speak in jest : joke

I was only fooling

3

: to contend or fight without serious intent or with less than full strength : toy

a dangerous man to fool with

transitive verb

1

: to make a fool of : deceive

2

obsolete : infatuate

3

: to spend on trifles or without advantage : fritter

—used with away

Synonyms

Noun

• lunatic [informal]
• idiot
• moron
• goose
• maniac [informal]

Adjective

• foolish
• stupid
• silly
• mad
• absurd
• insane
• crazy

Verb

• deceive
• trick

Examples of fool in a Sentence

Noun

those fools who ride motorcycles without wearing helmets

Only a fool would ask such a silly question.

You'd be a fool to believe what he tells you.

You're making yourself look like a fool.

Adjective

The dog was barking its fool head off.

Some fool driver kept trying to pass me!

Verb

When she first told us that she was getting married, we thought she was fooling.

His disguise didn't fool anybody.

He really had me fooled.

Stop fooling yourself—she doesn't really love you.

Recent Examples on the Web

Noun

President Trump has repeatedly called Federal Reserve Board Chair Jerome Powell stupid, terrible, a fool, and referred to him as a person of average mentality. —Mike Patton, Forbes.com, 30 June 2025

That fool’s from my family’s hometown over there in Mexico. —Carlos De Loera, Los Angeles Times, 19 June 2025

Verb

While denim remains a primary component of global fashion at every price point, don’t let its ubiquity and casual vibe fool you. —Simon Mainwaring, Forbes.com, 30 June 2025

But don’t let its impressive storage space fool you — the case folds in on itself to create a compact roll that’s easy to stow in suitcases and handbags. —Clara McMahon, People.com, 28 June 2025

Word History

Etymology

Noun, Adjective, and Verb

Middle English, from Anglo-French fol, from Late Latin follis, from Latin, bellows, bag; akin to Old High German bolla blister, balg bag — more at belly

First Known Use

Noun

13th century, in the meaning defined at sense 1

Adjective

13th century, in the meaning defined above

Verb

circa 1529, in the meaning defined at intransitive sense 1a

Phrases Containing fool

• act/play the fool
• a doddering old fool
• a fool and his money are soon parted
• a fool for
• any fool
• April fool
• fool about
• fool about with
• fool around
• fool around with
• fool of a
• fool's cap
• fool's errand
• fool's gold
• fool's paradise
• fool's parsley
• fool with
• make a fool of oneself
• make a fool (out) of
• not fool about
• not fool around
• (the) more fool one
• there's no fool like an old fool

Rhymes for fool

• boule
• brule
• buhl
• cool
• drool
• ghoul
• mule
• pool
• poul
• rule
• school
• spool

Kids Definition

fool

1 of 2 noun

ˈfül 

1

: a person who lacks good sense or judgment

2

: a person formerly kept in a noble or royal household to amuse with jests and pranks

fool

2 of 2 verb

1

a

: to spend time idly

just fooling around

b

: to meddle or tamper thoughtlessly or ignorantly

don't fool with that dial

2

: to speak or act in fun : joke

I was only fooling

3

: to make a fool of : trick