Etymology of "wacko"

[Joel S. Berson]

OED2:  wack (n):  An eccentric or crazy person; a madman, a crackpot.
    1938 'E. Queen' Four of Hearts (1939) i. 9 All you wacks act this
way at first. Them that can take it snaps out of it.

OED2 dates "wacky (a)"from 1935.

But -- the -o seems to be derived not only from adjectives with
negative connotations, but also from (the first syllable of) nouns,
as in "klepto", from "kleptomaniac"?

Joel

At 1/30/2006 09:28 AM, RonButters wrote:
Thanks for the explanation. I somehow missed the step that e.g.
STINKO is immediately derived from STINKY, not STINK. Still, in that
case, how is WACKY derived from WACK? What is a "wack"? Didn't that
have something to do with women in the army during WWII?

------------------------------------------------------------
The American Dialect Society - http://www.americandialect.org