cloak'- room, n. : A room near the entrance of any place of assembly, in which cloaks, coats, hats, etc., may be left; also, in recent use, an office at railway-stations, etc., where luggage of any description is temporarily taken charge of. Also freq. euphem. = lavatory n.
--- Oxford English Dictionary
Well, so in the United States, we are often regaled with political stories of "behind the scenes" deals that are worked out in the cloakroom of the Senate or the House of Representatives. And I have to say, I always pictured these deals being negotiated while -- oh, let's imagine Lindsay Graham and Al Franken huddled together, seated uncomfortably on a big pile of galoshes, and surrounded by the heavy woolen overcoats of Barbara Milkulski and John McCain and Mitch McConnell.
Let's all pause a moment and picture that.
But it turns out that the euphemism cloakroom has its origins in the medieval truth that the heavy woolen cloaks and capes that everyone wore were difficult to launder, and were infested (like everything else) with fleas and lice. According to Lucy Worsley, chief curator of the British non-profit Historic Royal Palaces, and author of If Walls Could Talk, the solution was to hang cloaks and capes in the privy -- also called the close-stool, or garderobe (according to the O.E.D: French: a place where clothes and other items are stored [from guard robes] and also a medieval toilet). The widespread belief was that the ammonia that rose up from the urine in the privy would kill the fleas and lice infesting the cloak.
So -- to this day, cloakroom is another euphemism for toilet or bathroom or lavatory or powder room or necessary or W.C. (water closet) or latrine or privy or jakes or . . . . What I have actually discovered is that every word that we use for "the room in which people perform bodily excretion" is a euphemism: a word that someone somewhere along the way thought was a classier, more discreet word than the one their parents used.
It's something to think about when next you hear Speaker of the House Paul Ryan pronounce on television, "I met with my Republican colleagues in the cloakroom . . . "