1. Broadax: 1 n a large ax with a broad cutting blade Synonyms: Broadaxe Types: battle-ax , battle-axe a Broadax used as a weapon Lochaber ax a battle-ax formerly used by Scottish Highlanders poleax , poleaxe a battle ax used in the Middle Ages; a long handled ax and a pick Type of: ax , axe an edge tool with a heavy bladed head mounted across a