booby trap

UK: /ˈbuːbi/ US: (bo̅o̅′bē trap′)

Inflections of 'booby trap' (v): (⇒ conjugate)

booby-traps

v 3rd person singular

booby-trapping

v pres p

booby-trapped

v past

booby-trapped

v past p

WordReference Random House Learner's Dictionary of American English © 2026

ˈboo•by ˌtrap, n. [countable]

1. Military a hidden bomb set off when a person who does not know it is there steps on it, touches a wire, or the like:
   used a metal detector to search for booby traps.
2. any hidden trap set for a person who does not expect it:
   The booby trap—a bucket of cold water over the partly open door—caught the next person who came in.

boo•by-trap, -trapped, -trap•ping, v. [~ + object]

to booby-trap a jungle path.

WordReference Random House Unabridged Dictionary of American English © 2026

boo′by trap′, 

1. Military a hidden bomb or mine so placed that it will be set off by an unsuspecting person through such means as moving an apparently harmless object.
2. any hidden trap set for an unsuspecting person.
• 1840–50

boo•by-trap  (bo̅o̅′bē trap′), v.t., -trapped, -trap•ping. 

1. Military to set with or as if with a booby trap;
   attach a booby trap to or in.

• 1940–45

Collins Concise English Dictionary © HarperCollins Publishers::

booby trap noun

1. a hidden explosive device primed in such a way as to be set off by an unsuspecting victim
2. a trap for an unsuspecting person, esp one intended as a practical joke, such as an object balanced above a door to fall on the person who opens it

verb (booby-trap, -traps, -trapping, -trapped)

1. (transitive) to set a booby trap in or on (a building or object) or for (a person)