Late 18th century; earliest use found in John Sinclair (1754–1835), agricultural improver, politician, and codifier of ‘useful knowledge’. From Scotch + gale.
Definition of Scotch gale in US English:
Scotch gale
noun
rare
Bog myrtle, Myrica gale.
Origin
Late 18th century; earliest use found in John Sinclair (1754–1835), agricultural improver, politician, and codifier of ‘useful knowledge’. From Scotch + gale.