hypnagogue

/ˈhɪpnəˌɡɑɡ/
noun
  1. Something that induces sleep or drowsiness.
    • Warm milk is often considered a natural hypnagogue.
    • The soft rain outside was a gentle hypnagogue that helped her fall asleep.
    • Some people find the sound of a fan to be a reliable hypnagogue.
Antonyms
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