warren |ˈwôrən, ˈwä-| noun (also rabbit warren) a network of interconnecting rabbit burrows. • a densely populated or labyrinthine building or district: a warren of narrow gas-lit streets. • Brit. historical an enclosed piece of land set aside for breeding game, esp. rabbits. ORIGIN late Middle English: from an Anglo-Norman French and Old Northern French variant of Old French garenne ‘game park,’ of Gaulish origin.