Q: I tuned in during your discussion of the word “cockamamie.” I didn’t hear the whole thing, but the word sounds like a Yiddishism to me.
A: I agree that “cockamamie” (it means “worthless” or “nonsensical”) sounds like a Yiddishism, but it seems that it’s not. The Random House Historical Dictionary of American Slang says it comes from “decalcomania” (the practice of using decals as cheap fake tattoos). According to Random House, “cockamamie” was the Brooklynese pronunciation of “decalcomania.” You can see the connection if you think of “cockamamie” as not only worthless or nonsensical but fake as well (the tattoo is a cheap imitation).
Another listener looked up “cockamamie” in Leo Rosten’s The Joy of Yiddish. Rosten says the word “is not Hebrew and not Yiddish, but indigenous argot.” He adds that people on the Lower East Side of Manhattan called the decal tattoos “cockamamies” because they didn’t know how to spell “decalcomania.”