There are 2 definitions of boo in English:

boo1

Syllabification: boo
Pronunciation: /bo͞o
 
/

exclamation

1Said suddenly to surprise someone: “Boo!” she cried, jumping up to frighten him
[probably an alteration of earlier bo, used in the same way since late Middle English]
More example sentences
  • Behind the church, right at the back of the graveyard (a graveyard I used to have to walk past in the dark with a sadistic little sister who thought it funny to say boo) is a tiny ruin.
  • I kept looking at them, waiting for a face to appear, to say hi or boo.
  • Ethan looked kind of nervous, I had the sudden urge to jump up and scream boo just to see what he'd do.
2Said to show disapproval or contempt, especially at a performance or athletic contest.
More example sentences
  • Unfortunately, one of the curtain rod kits I'd bought didn't have the mounting hardware inside, so I'm going to have to get another one - boo!
  • I have to get the whole broken on-off button on my cell phone seen to or else buy a new phone - boo!
  • Bianca gets every day except Tuesday off coz she's doing her IT subjects via distance. boo!

noun

Back to top  
An utterance of “boo” to show disapproval or contempt: the audience greeted this comment with boos and hisses
More example sentences
  • As Moore shouted over boos and cheers, most of the nominees who had just given him a standing ovation sat silent.
  • As the march swung past Number 10 there was a cacophony of whistles, boos, jeers and insults.
  • Shouts, boos, whistles from the crowd sheltering in the marquees.

verb (boos, booing, booed)

Back to top  
Say “boo” to show disapproval or contempt: [no object]: they booed and hissed when he stepped on stage [with object]: I was practically booed off the stage for talking about cyberpunk
More example sentences
  • Angry crowds attended public meetings organised by the Commission, jeering and booing the speakers.
  • Before he could finish, the crowd showed their disapproval by booing him off the stage.
  • Raymond actually booed when they disappeared off the right edge of the monitor.
Synonyms

Origin

early 19th century (sense 2 of the exclamation): imitative of the lowing of oxen. The sound was considered to be derisive; compare with hiss and hoot.

Phrases

say boo

[with negative] Say anything at all; utter a sound: Walter looked at us, but he didn’t say boo
More example sentences
  • Now he knows that all he has to do is pop up and say boo once in a while and we'll go all to pieces.
  • They just go out and do their job, don't say boo and everyone gets the point.
  • I have to go back to work tomorrow (this is where I won't say boo!)

wouldn't say boo to a goose

British Used to emphasize that someone is very shy or reticent.
More example sentences
  • My youngest son wouldn't say boo to a goose and he was absolutely petrified.
  • It turns out that the lad who looks like a no-nonsense squaddie on the park wouldn't say boo to a goose outwith those environs.
  • ‘He was quite a quiet guy who kept himself to himself - you always got the impression he wouldn't say boo to a goose,’ said Mr Hemmings.

Definition of boo in:

Get more from Oxford Dictionaries

Subscribe to remove adverts and access premium resources

Word of the day impudicity
Pronunciation: ˌɪmpjʊˈdɪsɪti
noun
lack of modesty

There are 2 definitions of boo in English:

boo2

Syllabification: boo
Pronunciation: /bo͞o
 
/

noun

US informal
A person’s boyfriend or girlfriend.
More example sentences
  • Some things I view as sacred and extremely personal that I wouldn't share… these include times shared with my boo.
  • ‘I'm not doubting what happened, boo,’ Shayna began sweetly.
  • She has also made solo inroads, doing that song about being with her boo.

Origin

1980s: origin uncertain; probably an alteration of French beau 'boyfriend, male admirer'.

Definition of boo in: