Claptrap now means nonsense or rubbish in the sense of meaningless and empty talk but it only acquired this meaning early in the 19th century. Its original and now archaic meaning dates from the early 18th century and derives from the theatre. Claptrap was originally a theatrical trick employed by people who managed or owned theatres. It was literally a trap or snare to encourage the audience to clap. For example, a long, dramatic pause from an actor at the end of a passage or scene was a clap trap that could encourage applause from the audience, but to make sure, theatres would also plant accomplices in the audience i.e. ‘clap traps’ who would start clapping to encourage the audience to follow suit.