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boo

interj. · v. · n.
US //ˈbu// UK //bˈuː// boo
  1. 1 to scare someone (interj.)
    A2 Elementary

    a word you shout suddenly to surprise or scare someone as a joke.

    an exclamation used to startle or frighten someone, typically in a playful or sudden manner.

    Example

    I hid behind the door and jumped out shouting boo when my brother walked in.

    Example

    The children spent the afternoon hiding in the garden, waiting for the perfect moment to jump out and yell boo at their unsuspecting parents.

  2. 2 showing disapproval (interj.)
    B1 Intermediate

    a sound made by a crowd to show they do not like a person or a performance.

    an exclamation used by an audience to express derision, disapproval, or dissatisfaction with a performance or speaker.

    Example

    The crowd shouted boo when the referee made a bad decision.

    Example

    A chorus of booing erupted from the gallery as the politician attempted to justify the controversial new tax policy.
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  1. 3 to shout disapproval (v.)
    B1 Intermediate

    to shout the word 'boo' at someone because you think they are doing a bad job.

    to express strong disapproval or derision by shouting the word 'boo' at a person or group.

    Example

    Fans began to boo the home team after they lost their third game in a row.

    Example

    Despite the actor's best efforts, the audience continued to boo throughout the final act of the play.

    Usage

    Often used as a transitive verb taking a direct object representing the person being criticized.
  2. 4 romantic partner (n.)
    B2 Upper Intermediate American English Slang Informal

    a slang word for a boyfriend, girlfriend, or someone you love.

    a term of endearment for a significant other or romantic partner.

    Example

    I am going to the cinema tonight with my boo.

    Example

    She posted a photo on social media of herself and her boo celebrating their first anniversary at the beach.

    Teacher's tip

    This term is very common in modern pop music and social media, but it should be avoided in any professional or academic context.
Etymology 1

From earlier (15c.) boh, coined to create a loud and startling sound. Compare Middle English bus! (“bang!”, interjection), Latin boō (“cry aloud, roar, shout”, verb), Ancient Greek βοάω (boáō, “shout”, verb).

Etymology 2

From beau, from French beau. First appears c. 1988 in the Washington Post: See the cite below.

Etymology 3

Of unknown origin, possibly from boojum, from a fancied resemblance of the plants. First appears c. 1959 in Esquire Magazine.

Etymology 4

Likely onomatopoeic.

Etymology 5

Dubious; perhaps adaptation of French beau (“beautiful”).

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