list·less 
(lĭstlĭs)
(lĭstlĭs)adj.
1. Lacking energy or disinclined to exert effort; lethargic: felt tired and listless.
2. Characterized by a lack of energy or interest: a listless glance.
[Middle English listles : probably from liste, desire (from listen, to desire; see LIST5) + -les, -lesse, -less.]
listless·ly adv.
listless·ness n.