Meaning

noun whiskey illegally distilled from a corn mash

noun the part of a boot above the instep

verb sell illicit products such as drugs or alcohol

originFrom boot + leg. Originally a nickname given to smugglers in King George III's reign, derived from the smugglers' custom of hiding packages of valuables in their large sea-boots when dodging the king's coastguardsmen.

Etymology from Wiktionary, CC BY-SA 3.0