c.1378, "piece of land enclosed for breeding beasts and fowls," from Anglo-Fr. and O.N.Fr.
warenne, O.Fr.
garenna "game park," possibly from Gaulish
*varenna "enclosed area," related to
*varros "post." Or the O.Fr. forms may derive from the prp. of O.Fr.
warir "defend, keep," from the Gmc. root
*war- "to protect, guard" (source of O.E.
warian "take care;" see
warrant (n.)). Later esp. "piece of land for breeding of rabbits" (c.1400), which led to the transf. sense of "cluster of densely populated living spaces" (c.1649).