Dear Word Detective: From whence is the word “drum” derived, as used in London English slang for a flat (an apartment) or house, often heard as “Come round to my drum” or “Let’s go over to your drum”? Similarly, why is a wristwatch referred to as a “kettle”? -- Andrew Houston, Kent, England.
Not so fast, buckaroo. You know darn well that's actually three questions, since I can't get away with explaining "drum" and "kettle" without delving into "flat" for our non-Brit readers.
While few Americans not permanently addled by overexposure to PBS routinely refer to their apartments as "flats," it has been standard usage in Britain since the 19th century. One might logically assume that, because most "flats" occupy a single story of a building, the word simply comes from the "flatness" of the abode, and one would be largely correct. But "flat" in this sense is actually derived from the obsolete Scots word "flet," meaning "floor" or "interior of a house" back in the 15th century. Then again, that "flet" was derived from the same Germanic root as our modern adjective "flat," so you can probably safely ignore that little Scottish detour.
"Drum" as slang for "flat" or "home" is, however, a bit less straightforward. The Oxford English Dictionary seems to think that this usage is derived in some mysterious fashion from the musical instrument sense of "drum," dating to the 16th century and derived from the German "trommel." But the eminent etymologist of slang Eric Partridge felt that this 19th century slang use of "drum" to mean "home" probably came from the Romany word "drom," meaning "road" (possibly derived from the Greek "dromos"). A slang sense of "drum" as "road" did indeed appear in early 19th century England, and the "home" sense was probably an outgrowth of this usage. The Romany origin of "drum" also makes sense, as Romany was the language of the Gypsies who played an important role in the underworld of 19th century London.
"Kettle" in the "big pot" sense is a very old word, derived from the Latin "catinus," meaning "deep pan for cooking." The use of "kettle" to mean "watch" first appeared in the argot of thieves in the 19th century, and apparently first referred to the large pocket watches popular at that time. The shape and heavy metal construction of old pocket watches makes likening them to kettles only a slight stretch, and a thief specializing in watches was known in the early 20th century as a "kettle banger."