French letter

Slang for condom dates from the mid-19th century because condoms back then were folded like envelopes and were described as French because of the prevalent British notion that anything to do with sex must have French origins. In fact, the first condoms to be made from rubber during the 19th century were from America. The French retaliated, however, by calling a condom une capote Anglaise, an English bonnet. Usage of French letter is now almost obsolete and if used at all it is generally referred to as a Frenchie.