grog

As a verb grok

is to have or to have acquired an intuitive understanding of; to know (something) without having to think (such as knowing the number of objects in a collection without needing to count them: see subitize).

As a noun grog is

an alcoholic beverage made with rum and water, especially that once issued to sailors of the Royal Navy.

As nouns the difference between grog and groghouse

is that grog is (label) an alcoholic beverage made with rum and water, especially that once issued to sailors of the royal navy while groghouse is (dated|rare) an inn where grog can be bought.