In Scottish folklore a woman of the human race who has been put under enchantments. She appears as a thin little woman with long yellow hair that reaches to her heels, wearing a green dress. Her face is wan and grey, whence her name glaistig, from glas, "grey." She is also called a glaistig uaine ("the green glaistig") from her wan looks and dress of green.
The glaistig haunts certain sites and farms, and sometimes watches over the house or the cattle, and confines herself to servant's work. She seems to have had a special interest in the cows and the dairy, and to have resented any want of recognition of her services. A portion of milk was set apart for her every evening, and unless this was done, something was found amiss in the dairy the next morning. Her strength was greater than that of any of the fairy race. She was seldom seen and was solitary in her habits.
- Campbell, J.G. (1900). Superstitions of the Highlands and Islands of Scotland. Glascow: James MacLehose and Sons, pp. 44-45, 155-156.