From King Dictionary of Contemporary Englishjohnjohn /dʒɒn $ dʒɑːn/ noun [countable] American English informal 1 TOILETa toilet2 SYthe customer of a prostitute
Examples from the Corpus
johnDownstairs I find a through room, a kitchen and a john.We got a hotel room that featured peeling paint, no windows, and a john in the shower stall.Two or three are always missing, out to lunch, or in the john, or wandering around the building.
Origin john (1900-2000) John, male name