boo

1 of 4

interjection

used to express contempt or disapproval or to startle or frighten

boo

2 of 4

noun (1)

plural boos
1
: a shout of disapproval or contempt
2
: any utterance at all
usually used in negative constructions
never said boo

boo

3 of 4

verb

booed; booing; boos

intransitive verb

: to deride especially by uttering a prolonged boo

transitive verb

: to express disapproval of by booing
the crowd booed the referee

boo

4 of 4

noun (2)

plural boos
US slang
: a romantic partner : sweetheart, honey
Your parents might keep a sharp eye on potential partners and your besties may lay down difficult "friend tests," but only one real opinion on your new boo truly matters: what your dog thinks of them.Jaime Lees
This has left me skeptical of all new relationships—including my new boo.Griffin Wynne

Examples of boo in a Sentence

Noun (1) A chorus of boos was heard after the shot missed the goal. The announcement was greeted by a mixture of boos and cheers. Verb Many people in the crowd booed when the announcement was made. Many people in the crowd booed the announcement, but a few people cheered it.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Interjection
Williams also recalled witnessing the Super Bowl crowd boo Taylor Swift when she was shown on the jumbotron cheering on her boyfriend, Kansas City Chiefs player Travis Kelce. Wesley Stenzel, EW.com, 17 Apr. 2025 Highlights include a costume parade (for kids and parents), a Purim story and boo Haman and songs. Linda McIntosh, San Diego Union-Tribune, 15 Mar. 2024
Noun
But Cody Rhodes quickly became the de facto heel by exploiting Orton’s back injury early in the match, which garnered boos. Alfred Konuwa, Forbes.com, 28 June 2025 His adventure resulted in him getting the bat, bringing cheers, being escorted out by security, bringing boos, and then returning to his seat, bringing a loud ovation and high-fiving from fellow fans. Paul Sullivan, Chicago Tribune, 20 June 2025
Verb
Opposition to Johnson’s selection was evident before Wednesday’s unanimous board vote, as members of the audience booed when her nomination was introduced. Dara Kam, Sun Sentinel, 18 June 2025 Earlier this week, Trump raised eyebrows during a speech at Fort Bragg when members of the 82nd Airborne Division, who were directed to stand behind Trump, booed and cheered during his incendiary remarks, including condemnation of his predecessor Joe Biden. Lolita C. Baldor, Arkansas Online, 15 June 2025 See All Example Sentences for boo

Word History

Etymology

Interjection

expressive formation; the voiced labial release and high vowel presumably heighten the suddenness of the utterance

Noun (1)

derivative of boo entry 1

Verb

derivative of boo entry 2

Noun (2)

of uncertain origin

Note: Perhaps ultimately a hypocoristic reduction of brother, applied to unrelated males, but the details are unclear.

First Known Use

Interjection

1639, in the meaning defined above

Noun (1)

1884, in the meaning defined at sense 1

Verb

1833, in the meaning defined at intransitive sense

Noun (2)

1988, in the meaning defined above

Time Traveler
The first known use of boo was in 1639

Browse Nearby Words

Cite this Entry

“Boo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/boo. Accessed 4 Jul. 2025.

Kids Definition

boo

1 of 2 interjection
used to express contempt or disapproval or to startle or frighten

boo

2 of 2 noun
plural boos
1
: a shout of disapproval or contempt
2
: any sound at all
never said boo
boo verb

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