1. Sleep inducing
   - soporific, soporiferous, somniferous, hypnogogic, hypnagogic

See also: depressant

• prolactin
• prolamine
• prolapse
• prolapsus
• prolate
• prolate cycloid
• prole
• proleg
• prolegomenon
• prolepsis
• proletarian
• proletariat
• proletariate
• proliferate
• proliferation
• proliferous
• prolific
• prolificacy
• prolifically
• proline
• prolix
• prolixity
• prolixly
• prolixness
• prolocutor