Sexyadj. /ˈsɛksi/ From sex (Middle French sexe < Latin sexus (“gender”); thought to be connected with Latin seco, secare (“divide, cut”) by the concept of division, or “half” of the race) + -y — 1: sexually suggestive or stimulating; erotic. 2: generally attractive or interesting; appealing.
Desirableadj. /di-ˈzī-rə-bəl/ From desire (Middle English desiren < Old French desirer < Latin desiderare, orig., prob., to await from the stars < de-, from + sidus, star) + -able — 1: having pleasing qualities or properties; attractive. 2: worth seeking or doing as advantageous, beneficial, or wise; advisable.
Consider Penélope Cruz: There’s no doubt she’s one of the most beautiful women in the world today. Sexy, yes, beyond shadow of a reasonable doubt. But without unnecessarily vilipending Ms. Cruz (since I don’t know her personally) — is she really desirable?
A certain kind of trousered ape, a type all too familiar to us, would answer, “Well, yeah! Duh! Who wouldn’t like to wake up to that in the morning?” This is precisely the attitude that gets us the perennial female complaint, “Men are pigs!” And, unfortunately, even the best of us aren’t so far from the trousered ape that we don’t wonder what Ms. Cruz would look like with bed hair, no makeup and the sleep still in her eyes.