drowsy

adjectives

half asleep

"made drowsy by the long ride"; "it seemed a pity to disturb the drowsing (or dozing) professor"; "a tired dozy child"; "the nodding (or napping) grandmother in her rocking chair"

dozy, drowsing, drowsy

is derived from

drowse

is derived from

drowsiness

showing lack of attention or boredom

"the yawning congregation"

drowsy, oscitant, yawning