somniative
/ˌsɒmniˈætɪv/; /ˌsɒmniˈeɪtɪv/Definitions
1. adjective
tending to induce or promote sleep
“The somniative effects of the medication helped her fall asleep quickly.”
2. noun
a somniative agent or substance
“Lavender oil is used as a somniative in aromatherapy.”
3. adverb
in a way that induces or promotes sleep
“She slept somniatively after the long walk.”