Definition of "gentlemen's"

A gents' toilet room might be found in a house that caters for the cheaper class of theatrical patronage, where the slangy language of the "goin' to the mat this aft?" style prevails. A gents toilet room is not found in the Southern Hotel. It either "men's" or "gentlemen's".

1898, The Hotel/Motor Hotel Monthly, volume 6, page 27

Over on that platform's the general waiting-room,... and over there's the Gentlemen's, and, any'ow, everythink's written up.

1933, James Ian Arbuthnot Frazer as "Shamus Frazer", Acorned Hog, page 78

"I tell you what I must do, is to telephone. Where is it?""D'you mean really the telephone or the gentlemen's?"

1934, Evelyn Waugh, chapter III, in Handful of Dust, page 117