booby-trap
noun, verb

- an explosive device designed to be triggered when an unsuspecting victim touches or disturbs a seemingly harmless object

- a situation that catches one off guard; a pitfall, a trap

(The American Heritage Dictionary)

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The word "booby" has been used since at least the late 17th century to mean fool or idiot. It has been suggested that it stems from the Spanish "bobo," which translates to a stupid person, a fool, a simpleton.

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 fool.

Booby has also been applied to a species of sea bird (Sula), 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.

Booby-trap was originally used in the sense of a situation or trap that surprises someone, but doesn't necessarily cause physical harm. After World War I, when land mines became a common tool of war, booby-trap took on the additional meaning of a harmless-looking device containing a concealed explosive designed to injure, maim or kill.

Another type of booby-trap is the roadside bomb, which the military calls improvised explosive devices (IED). IEDs were commonly used by Iraqi insurgents after the U.S. invasion in 2003.

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SYNONYMS

ambush, pitfall, baited trap, decoy, hidden danger, set-up, snare, trip-wire

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SMUGGLE OWAD into today's conversation, say something like:

"For a pessimist, life is full of BOOBY-TRAPS!"