trap-door的词源解释,trap-door来源

"door set flush in a floor or ceiling," often hidden and leading to a passageway or secret place, late 14c., trappe-dore; see trap (n.1) + door (n.). Trap-door spider, in reference to one of several formidable-looking species whose nest is a tube in the soil with a hinged lid like a trap door, is attested by 1835. The tube is for the spider's concealment and safety, not to capture prey.

该词起源时间：14世纪末