Means "uncle", from Hebrew אָח ('ach) "brother" and אֲב ('av) "father". This was the name of a king of Israel, the husband of Jezebel, as told in the Old Testament. He was admonished by Elijah for his sinful behaviour. This name was later used by Herman Melville in his novel 'Moby-Dick' (1851), where it belongs to a sea captain obsessively hunting for a white whale.