Reminded of one misconception I saw come up again recently, by one wtfduolingo post I reblogged earlier.

I don’t recall running across the word in Swedish before, oddly enough, but I wasn’t surprised that it’s “dum” and “dummare”.

Compare to “dumm” and “dümmer” in German. Which got snagged into American English from the huge number of German-speaking immigrants.

(Where “mute/silent” is “stumm”, BTW, with a totally different etymology. That incidentally got taken into British English, as “keeping schtum”. Snitches get stitches…)

Speaking of very direct usage adoption, as Mencken observed in the 1920s:

Dumb-head, obviously from the German dummkopf, appears in a list of Kansas words collected by Judge J. C. Ruppenthal, of Russell, Kansas. (Dialect Notes, vol. iv, pt. v, 1916, p. 322.) It is also noted in Nebraska and the Western Reserve, and is very common in Pennsylvania.

Dumb still not really used in that sense in British English–or probably other versions–which is likely why Duolingo opted for the “stupid” and “more stupid” translation there. (Which kinda jumped out at me, when “dumb” and “dumber” is a less clunky rendering. Better to use something more readily understood across dialects, though.)

People are certainly welcome to a variety of opinions on the advisability of those descriptions anyway, of course. But, the real etymology isn’t what it’s often assumed to be. Because English, and alleyways.