While culinary historians debate its exact lineage, most agree eggnog originated from the early medieval Britain “posset,” a hot, milky, ale-like drink. ... Some say “nog” comes from “noggin,” meaning a wooden cup, or “grog,” a strong beer. By the late 18th century, the combined term “eggnog” stuck.

What does the nog stand for in eggnog?

The Online Etymology Dictionary states that the term "eggnog" is an American term introduced in 1775, consisting of the words "egg" and "nog", with "nog" meaning "strong ale".

Why is eggnog so bad for you?

But as with many holiday treats, eggnog—traditionally made with eggs, cream, milk, and sugar—is loaded with calories, fat, and added sugars. And there's an additional health concern with eggnog: If it's made with raw eggs, it can be a food-poisoning risk.