hoar frost. This was one of the words that Burns seemed to favour when he wanted to create a sense of suffering in the bitter cold. Perhaps his best-known use of the word is in To a Mouse, when his accidental destruction of the mouse’s nest leaves the mouse exposed to the Winter’s sleety dribble An cranreuch cauld.
It is also used figuratively as in:
Full eighty winters thick hae spread
Their cranreughs o’er my palsied head
(George Beattie Drama of John o’ Arnha 1816).