Antonyms of noun hypersomnia

1 sense of hypersomnia

Sense 1
hypersomnia -- (an inability to stay awake)
       Antonym of insomnia (Sense 1)
      => insomnia -- (an inability to sleep; chronic sleeplessness)

Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun hypersomnia

1 sense of hypersomnia

Sense 1
hypersomnia -- (an inability to stay awake)
       => sleep disorder -- (a disturbance of the normal sleep pattern)