The Collaborative International Dictionary of English v.0.48:
Slumbery \Slum"ber*y\, a. Sleepy. [Obs.] --Chaucer. [1913 Webster]WordNet (r) 3.0 (2006):
slumbery adj 1: inclined to or marked by drowsiness; "slumberous (or slumbrous) eyes"; "`slumbery' is archaic"; "the sound had a somnolent effect" [syn: slumberous, slumbery, slumbrous, somnolent]