Boo
/buː/noun
An interjection used to startle someone, express disapproval, imitate a ghost, or address a romantic partner.
Did you know?The startling interjection has no securely established ancient root and is generally treated as expressive or imitative, while the romantic sense is commonly connected with French beau, meaning “boyfriend” or “admirer.”
Etymological Timeline
16th Century
English
bo
“An attested interjection used to frighten or startle someone; its ultimate origin is uncertain.”
18th Century
English
boo
“A form used as a cry intended to frighten, especially in contexts involving ghosts or sudden appearances.”
19th Century
English
boo
“An exclamation expressing disapproval, especially from an audience.”
19th–20th Century
English
boo
“A term of affection or a romantic partner, probably influenced by French beau, “boyfriend” or “admirer.””
Modern English
English
boo
“A startling cry, a hostile audience reaction, or an informal affectionate name for a partner or close person.”
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