Quote: "As for scumbag, I’m dumbfounded—and also just plain dumb I guess. I was totally ignorant of its vulgar side." Crossword puzzle writer Lynn Lempel in Haloscan.
Figure of Speech: cacemphaton (cak-EM-pha-ton), foul language. Also polyptoton (po-LIP-to-ton), the root-word repeater.
The answer to 43 Down in Monday’s New York Times crossword puzzle was SCUMBAG. That’s a cacemphaton ("foul sounding"), a nasty figure based on one of humanity’s oldest words: cak, meaning excrement.
The puzzle’s creator apologizes with a polyptoton, a figure that repeats the root of a word with a different word: "dumbfounded" (struck dumb; speechless) and "dumb" (stupid or ignorant).
Technically, though, "scumbag" only qualifies as a cacemphaton when the user (presumably an etymologist or someone over 50) knows the original definition: a used condom.
Snappy Answer: "Why, you knotty-pated fustilarian!"