boo

¹ American  

[boo] / bu /

interjection

1. (used to express contempt or disapprobation or to startle or frighten.)

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noun

boos plural

1. an exclamation of contempt or disapproval.

   a loud boo from the bleachers.

verb (used without object)

boos, present (3rd person singular) booed, past participle, past booing present participle

1. to cry boo in derision.

verb (used with object)

boos, present (3rd person singular) booed, past participle, past booing present participle

1. to show disapproval of by booing.

boo ² American  

[boo, boh] / bu, boʊ /

noun

1. Slang. marijuana.

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boo ³ American  

[boo] / bu /

noun

Slang.

1. one's boyfriend or girlfriend.

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boo British  

/ buː /

interjection

1. an exclamation uttered to startle or surprise someone, esp a child

2. a shout uttered to express disgust, dissatisfaction, or contempt, esp at a theatrical production, political meeting, etc

3. is extremely timid or diffident

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verb

1. to shout "boo" at (someone or something), esp as an expression of disgust, dissatisfaction, or disapproval

   to boo the actors

Usage

What else does boo mean? Boo is the sound we pretend ghosts make as well as a sound we make when we really don’t like something. Boo is also an affectionate term for one's significant other, similar to bae.

Other Word Forms

Inflected Forms

noun

• boos
  plural

Conjugated Forms

Present

• have booed
  perfect
• has booed
  perfect 3rd person singular
• are booing
  progressive
• have been booing
  perfect progressive
• is booing
  progressive 3rd person singular
• has been booing
  perfect progressive 3rd person singular
• am booing
  progressive 1st person singular
• boos
  singular 3rd person
• booing
  participle

Past

• had booed
  perfect
• had been booing
  perfect progressive
• was booing
  progressive singular
• were booing
  progressive plural
• booed
  participle
• booed
  simple

Future

• will boo
  simple
• will have booed
  perfect
• will have been booing
  perfect progressive
• will be booing
  progressive

Etymology

Origin of boo¹

First recorded in 1630–40; expressive formation

Origin of boo²

First recorded in 1955–60; of uncertain origin

Origin of boo³

1985–90; of uncertain origin; possibly an alteration of French beau “boyfriend, admirer”

Example Sentences

They grads are also primed to boo any speakers who so much as mutter the words “artificial intelligence.”

From Slate • May 20, 2026

"I'd boo me too," he posted winningly after more barracking from across the Channel.

From BBC • Apr. 30, 2026

Asked why opposition fans often boo Garnacho, he added: "Maybe it's because people judge a book by its cover."

From BBC • Apr. 12, 2026

Nowhere else do people boo like they do there.

From Los Angeles Times • Apr. 10, 2026

At the Home after grace was said we weren’t allowed to say boo.

From "Bud, Not Buddy" by Christopher Paul Curtis

Related Words

• heckle
• hiss
• holler
• hoot
• jeer