Adjective drowsy has 2 senses
  1. drowsy, drowsing, dozy - 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"
    Antonym: awake (indirect, via asleep)
  2. drowsy, oscitant, yawning - showing lack of attention or boredom; "the yawning congregation"
    Antonym: attentive (indirect, via inattentive)
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