The term eggnog evolved out of two slang words used in urban of colonial North America. Colonist referred to rum as grog; bartenders served rum in small wooden carved mugs called noggins. Thus the drink eventually became egg-n-grog and over time eggnog. When the American Revolution resulted in dwindling trade between North America and the Caribbean, Americans began to substitute locally distilled spirits or moon-shine for rum in their eggnog.
Eggnog Recipe Circa 1930s
Serves 1
Take one egg, separate white and yellow, add teaspoonful sugar to yellow and beat until light. Beat white until very stiff. Beat one to two tablespoonfuls charred keg corn whiskey into prepared yellow. This is supposed to "cook" the egg. Gradually beat in the white. Pour into tall glass and drink. Milk and whipped cream may be added to taste. (Notes, Reports, and Essays, South Carolina Folder, WPA Records, Library of Congress)