Glamour
early 18th century (originally Scots in the sense ‘enchantment, magic’): alteration of grammar. Although grammar itself was not used in this sense, the Latin word grammatica (from which it derives) was often used in the Middle Ages to mean ‘scholarship, learning’, including the occult practices popularly associated with learning.
wiktionary
Some say from Scots glamer, supposedly from earlier Scots gramarye(“magic, enchantment, spell”).
The Scottish term may either be from Ancient Greek γραμμάριον(grammárion, “gram”), the weight unit of ingredients used to make magic potions, or an alteration of the English word grammar(“any sort of scholarship, especially occult learning”).
A connection has also been suggested with Old Norse glámr (poet. “moon,” name of a ghost) and glámsýni(“glamour, illusion”, literally “glam-sight”). From Grettir's Saga aka Grettis Saga, one of the Sagas of Icelanders, after the hero has been cursed by Glam, aka Glamr:
"...he was become so fearsome a man in the dark, that he durst go nowhither alone after nightfall, for then he seemed to see all kinds of horrors.
And that has fallen since into a proverb, that Glam lends eyes, or gives Glamsight to those who see things nowise as they are."
Glamsight (glámsýni) is also referred to in the Icelandic collection Sturlunga saga.
etymonline
glamour (n.)
1720, Scottish, "magic, enchantment" (especially in phrase to cast the glamor), a variant of Scottish gramarye "magic, enchantment, spell," said to be an alteration of English grammar (q.v.) in a specialized use of that word's medieval sense of "any sort of scholarship, especially occult learning," the latter sense attested from c. 1500 in English but said to have been more common in Medieval Latin. Popularized in English by the writings of Sir Walter Scott (1771-1832). Sense of "magical beauty, alluring charm" first recorded 1840. As that quality of attractiveness especially associated with Hollywood, high-fashion, celebrity, etc., by 1939.
Jamieson's 1825 supplement to his "Etymological Dictionary of the Scottish Language" has glamour-gift "the power of enchantment; metaph. applied to female fascination." Jamieson's original edition (1808) looked to Old Norse for the source of the word. Zoëga's Old Icelandic dictionary has glám-sýni "illusion," probably from the same root as gleam.
glamour (v.)
1814, "to enchant, charm, bewitch," from glamour (n.). Related: Glamoured; glamouring.
