a budget of grammatical peeves

A discussion I had recently online about what peevologist meant (see this Wishydig blog entry for a discussion of its origin) revealed to me a great truth about soi disant snoots: they are as lacking in their quivering aggregate of absolutist rules of “grammar” as they are in their erudition and scholarship. (Well, perhaps I’d already had an inkling of that.) Their Weltanschauung causes them to hound anybody who uses a word with a slightly different meaning to the one which their grammar teacher beat into them, e.g., decimate to mean destroy. Any whiff of semantic drift causes the customary ejaculation “And look at how gay was co-opted! It used to mean merry or joyful!” Some say it still does in some contexts. I usually try to explain to them that gay has had a long and varied semantic drift since emigrating from Normandy to England about a millennium ago.
From Partridge A Dictionary of Slang and Unconventional English (in two volumes), Routledge & Kegan Paul, 1961:

Gay. (Of women) leading an immoral, or a harlot’s, life: 1825, Westmacott (OED), In C. 20, coll., on verge of SE.—2. Slightly intoxicated; ob. C.19–20; Perhaps orig. a euphemism.—3. Impudent, impertinent, presumptuous: US (—1899), anglicized in 1915 by PG Wodehouse, OED (Sup.).

Also, gay house ‘brothel’, gay in the arse ‘(Of women) loose’, to lead a gay life ‘to live immorally’, the gay instrument ‘the male member’, gaying it ‘sexual intercourse’.
The grammar mavens’ll have nothing of the sort, thankee. They’ll blink myopically and tell you that though they have nothing against homosexuals personally, but they do want their word back. Yeah, right. Why are similarly polysemous words like symbology not being ranted about? I count at least three meanings of the word: (1) The study of symbols; (2) the use of symbols; and (3) a collection or system of symbols. And don’t even ask them about mole or put.