soporific

Something that is soporific is sleep-inducing. Certain medicines, but also extreme coziness, can have a soporific effect.

In the 1680’s, soporific, which doubles as both adjective and noun, was formed from the French soporifique. That word, in turn, came from the Latin sopor β€œdeep sleep.” Beloved Peter Rabbit author Beatrix Potter once noted that, β€œIt is said that the effect of eating too much lettuce is 'soporific'."

Definitions of soporific
1

adj sleep inducing

Synonyms:
hypnagogic, hypnogogic, somniferous, somnific, soporiferous
depressant
capable of depressing physiological or psychological activity or response by a chemical agent

adj inducing mental lethargy

Synonyms:
narcotic, soporiferous
uninteresting
arousing no interest or attention or curiosity or excitement

n a drug that induces sleep

Synonyms:
hypnotic
Types:
narcoleptic
a soporific drug that produces an uncontrollable desire to sleep
sleeping capsule, sleeping draught, sleeping pill, sleeping tablet
a soporific drug in the form of a pill (or tablet or capsule)
Type of:
drug
a substance that is used as a medicine or narcotic
hypnagogue
an agent that induces drowsiness or sleep