Booby-trap

A booby trap is a device or setup that is intended to kill, harm or surprise a person, unknowingly triggered by the presence or actions of the victim. As the word trap implies, they sometimes have some form of bait designed to lure the victim towards it. At other times, the trap is set to act upon trespassers that violate personal or restricted areas. The device can be triggered when the victim performs some type of everyday action e.g. opening a door, picking something up or switching something on. They can also be triggered by vehicles driving along a road as in the case of victim-operated improvised explosive devices (IEDs).

Booby traps should not be confused with mantraps which are designed to catch a person. Lethal booby traps are often used in warfare, particularly guerrilla warfare, and traps designed to cause injury or pain are also sometimes used by criminals wanting to protect drugs or other illicit property, and by some owners of legal property who wish to protect it from theft. Booby traps which merely cause discomfort or embarrassment are a popular form of practical joke.

The Spanish word bobo translates to "stupid, daft, naïve, simple, fool, idiot, clown, funny man, one who is easily cheated" and similar pejorative terms. The slang of bobo, bubie, translates to "dunce". Variations of this word exist in other languages (such as Latin), with their meaning being "to stammer". Thus, the term "booby trap" gives rise to the idea that an individual with the misfortune to be caught in the trap does so because the individual is a "booby", or that an individual who is caught in the trap thereby becomes a "booby".

The word has also been applied to the Sula genus of sea birds, with their common name being boobies. These birds, adapted for sea flight and swimming, have large flat feet and wide wingspans, making it difficult for them to run or take flight quickly. As a result, they are considered clumsy and easy to catch when onshore. They are also known for landing aboard seagoing vessels, whereupon they have been eaten by the crew.

In approximately 1590, the word began appearing in the English language as booby, meaning "stupid person, slow bird".

The phrase booby trap originally applied to schoolboy pranks, but took on its more sinister connotation during World War I.

A military booby trap may be designed to kill or injure a person who activates its trigger, or employed to reveal the location of an enemy by setting off a signalling device. Most, but not all, military booby traps involve explosives.

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