Why are lethal device called “booby trap”?

The word boob means stupid or dunce was first used in 1599, it was taken from the Spanish word bobo also meaning stupid. The Spanish word originated from the Latin word Balbus. Also a booby prize is awarded to the biggest loser, it was during the First World War that the term changed meaning, from a harmless word it become a harmful one. Because of the deadly traps laid on the ground during the wartime, the word changed meaning and degree of the term changed too.

Did you know during the war, enemies would lure opposition soldier to the booby traps with a trap, they would often use comrades and wound them and force them to lure out their friends into the trap.