C16: so called because it is common on Scottish hills
Scotch mist in American English
noun
1.
a combination of mist or fog and drizzle, occurring frequently in Scotland and parts of England
2.
a cocktail made by pouring Scotch whisky over finely crushed ice
Word origin
[1655–65]This word is first recorded in the period 1655–65. Other words that entered Englishat around the same time include: flip-flop, grille, intensity, loaded, neutralize