You say that like it's a joke, but they're called mammals because they have mammae -- breasts, udders -- and although I don't know completely for certain I'd be

You say that like it's a joke, but they're called mammals because they have mammae -- breasts, udders -- and although I don't know completely for certain I'd be flabbergasted if Latin mamma weren't very directly related to mama etc. (Wiktionary says it's from Greek "mamme" which it alleges is a back-formation from babies' "mama", and cites a learned-sounding reference, but I don't know whether anyone actually has more than conjecture here.)