Medieval grammatica meant Latin learning, and since learning looked like magic to the unlettered, Old French gramaire doubled as spell-book, giving French grimoire and English gramarye, occult learning. Scots altered grammar to glamour in the early 1700s: Allan Ramsay's 1720 satire has Beelzebub casting his cheating Glamour over a witch's eyes; the glossary defines it plainly, when devils, wizards, or jugglers deceive the sight, they cast Glamour o'er the eyes. Walter Scott carried it south. By the mid-1800s the word shed the spell and kept the illusion: beauty that makes people feel enchanted, the modern sense.
Cornell's William Sayers challenges the whole grammar story: Scots glamour more plausibly descends from Old Norse glamr, the name of a poetic moon-spirit associated with delusion and, in the sagas, with the Celtic magic of mixed-race islanders who conjured vanishing halls and bewitched sleep. The Norse word even carries the same kinetic idiom, a spell cast over the victim's sight. Either lineage, the word was born as a weaponized illusion blamed on outsiders, Celtic satirists or Scottish travelers.
The claim: glamour's journey from curse to compliment is the pattern of every successful manipulation, the spell that gets accepted stops being called a spell, and the advertising industry, Hollywood, and influencer culture are the inherited practice with the Scots accusation laundered out; glamour is what the cast glamour calls itself after the audience stops resisting. Verdict: the dictionaries document the melioration. The archive's psyop wing files the mechanism under different names. Same casting, friendlier lighting.
If glamour is grammar wearing a disguise, what is the disguise made of, and who taught it to spell?