We found 3 dictionaries that define the word sleep onset:

General (1 matching dictionary)

1. Sleep onset: Wikipedia, the Free Encyclopedia

Medicine (2 matching dictionaries)

2. Sleep Terms (No longer online)

Definitions from Wikipedia (Sleep onset) ▸ noun:  the transition from wakefulness into sleep. Phrases: Sleep onset latency, more... ▸ Words similar to sleep onset ▸ Usage examples for sleep onset ▸ Idioms related to sleep onset ▸ Wikipedia articles (New!) ▸ Words that often appear near sleep onset ▸ Rhymes of sleep onset ▸ Invented words related to sleep onset