A drink made from rum mixed with water, especially as served to sailors in the British Navy.
Named after Admiral Vernon's nickname 'Old Grog' (from his grogram cloak), who ordered rum to be diluted with water in 1740 to make it last longer on ships. The drink became standard British naval issue.
Admiral Vernon nicknamed 'Old Grog' basically invented the drink when he cut the Navy's drinking budget by diluting rum—and his nickname became the word for the drink itself! This is a fun example of how one person's nickname can enter the dictionary.
Complete word intelligence in one call. Free tier — 50 lookups/day.