(Brief but penis-dense, so not to everyone’s taste; there are, alas, no images)
My morning name today — a natural for someone as phallically oriented as I am — was pillicock, according to the OED (revised 2006), an archaic BrE word for the penis. A penis word that actually vanished, as a reference to the male organ or any semantic development from that. This despite the fact that it truly contained cock ‘penis’ (the pilli part is etymologically obscure).
(Irrelevantly, my wind went on a dactylic jaunt — pillicock, petticoat, billygoat, jerry-built, marzipan — and from there to a delicious double dactyl, marzipan pillicock. A majestic almond-candy phallus; no doubt someone actually makes these. Or perhaps a sweet-tongued prick, that lying seducer Don Juan in his guise as Captain Marzipan Pillicock.)
I would have expected pillicock to have gone the way of pillock (entirely of obscure etymology), which the OED (revised 2006) tells us started out as
Originally Scottish. The penis. Now English regional (northern) and rare. [1st cite 1568]
But mostly went the way of prick and dick and putz and others in various languages, which went bad, went downhill semantically: pillock has ended up as
Chiefly British colloquial (mildly derogatory). A stupid person; a fool, an idiot. [1st cite 1967]
(And yes, morning wood word is an odd portmanteau of morning wood and morning word. Leading, I suppose, to thoughts of morning wood word and burn stein, morning burn being a novel alternative to razor burn. Ok, I’ll stop.)