I'm imagining the sleep equivalent of words like aphrodisiac, appetiser, etc.

For example:

Oysters are an aphrodisiac

Hot drinks are a {thing that makes one sleepy}

thesaurus.com doesn't give anything which leads to a suitable noun.


7 Answers 7


Most contemporary words have already been given, though 'hypnotic' is still used in pharmacology (as when distinguishing sleep-producing effects from sedation); the rest of these words are obscure.

  • hypnotic : a drug which produces sleep (i.e. sedative)
  • dwale : a stupefying or soporific drink (often specifically Belladonna) [TFD]
  • sopient : a soporific agent (medical) [OED]
  • somnifacient a drug or other agent that induces sleep.
  • somniferic : a soporific [seemingly conflated as another form of the adj somniferous, but cited as an obsolete noun by OED]
  • somnificator : a person who induces sleep [OED, rare]
  • somnivolency : a thing intended as a soporific (pl. somnivolencies) [OED, rare; a somnivolent is also one who desires] to sleep
  • somnoriferous/somnorific : adj. soporific, as said of an agent [OED, obs]
  • soporative : obs form of soporific [OED]

And a few more adjectives, since they can be easily made to refer to such a thing:

somniculous, somnific, somnifying, soporous,

  • This was most useful for me, given what I was trying to express. Thanks!
    – TSwire
    Commented Dec 3, 2014 at 1:59
  • What about, "the itis"? urbandictionary.com/define.php?term=the+Itis ; youtube.com/watch?v=rNh_mQo9fXo Commented Mar 25, 2015 at 17:08
  • @RenaissanceProgrammer: good call on the cultural reference, but it's on the wrong side of the concept in question. "The Itis" is really a synonym for the state of sleepiness, while the question asked for the general name of agents which cause this state. While ribs or turkey would be a specific example, the general class of sleep-promoting food might fall under something already mentioned, such as soporific. Commented Apr 17, 2015 at 4:07
  • @TwoSheds thanks for considering my suggestion. I rebuttal your statement with: I don't think "the itis" is really a synonym for the state of sleepiness because it is only brought on by consumption of said specific examples. One wouldn't say they have "the itis" after a long days work, therefore, I believe "the itis" is a cause, just like not everyone, nor every time, that you eat ribs or turkey, do you feel sleepy. Only in cases where one has contracted "the itis" does sleepiness start to incur. :-) Commented Apr 17, 2015 at 16:12
  • Yes, this is a good call again. Calling it a synonym is not necessarily precise: it's an example of a state of sleepiness, so is only a synonym in both directions if the causation meets criteria. But the point about it being on the wrong side of cause/effect still stands ^^ Commented Mar 18, 2017 at 4:04

Soporific, or soporiferous:

  • Inducing or tending to induce sleep.
  • Drowsy.


  • The professor’s boring speech was soporific and had everyone in the audience yawning.

  • Because of the medicine’s soporific properties, the doctor told me to only take it at bedtime.

  • 4
    The word is adjectival in form, but is often used as a noun to mean a soporific medicine, as in "She prescribed him a single dose of a potent soporific." Commented Nov 30, 2014 at 20:30
  • 4
    Yep, as soon as I saw the question I said "soporific". I think it's fairly well known and understood.
    – Hot Licks
    Commented Nov 30, 2014 at 21:55
  • 3
    Used in Beatrix Potter - The Flopsy Bunnies.
    – user60295
    Commented Nov 30, 2014 at 23:00
  • Like this answer?
    – tox123
    Commented Nov 30, 2014 at 23:45
  • 2
    @FrancisDavey Yes, it isn't used very much in real life.
    – user60295
    Commented Dec 1, 2014 at 19:12

'Sedative' is a word for a thing (substance, pill, medicine, drug) that makes one sleepy, because it induces (or tends to induce) sleep.

  • 1
    It also works for non-medications, like "Dr. Slocombe's lecture on the sociopolitical implications of foot fungus is an effective sedative."
    – fluffy
    Commented Nov 30, 2014 at 23:22
  • 8
    Sedation is the reduction of irritability or agitation. A sedative does not necessarily make you sleepy. Commented Dec 1, 2014 at 14:26
  • Depressant is what came to mind, as in the opposite of a stimulant (like caffeine) that keeps you awake, a depressant makes you tired.
    – Xen2050
    Commented Dec 3, 2014 at 14:24

You might like to consider

Dormitive - From Websters - A substance that causes sleep; a soporific.
Dormifacient - (Medical Term) That which brings about sleep or aids in attaining sleep; "a dormifacient agent".


Since you appear to be looking for a noun, I would say narcoleptic is your word.

  • This seems a good answer to the question. thefreedictionary.com/narcoleptic: a soporific drug that produces an uncontrollable desire to sleep. Commented Nov 30, 2014 at 22:17
  • 5
    IMO, "narcoleptic" is much stronger than just "makes you sleepy". "Hypnotic" or "soporific" are the better choices. Commented Dec 1, 2014 at 14:31
  • 5
    Use this one with caution: narcoleptic more often describes a person afflicted with narcolepsy. Such a person is prone to falling asleep, but a narcoleptic person doesn't cause anyone to feel sleepy. Without clarification, this could easily lead to confusion.
    – talrnu
    Commented Dec 1, 2014 at 18:57

One possibility is narcotic:

1 a : a drug (as opium or morphine) that in moderate doses dulls the senses, relieves pain, and induces profound sleep but in excessive doses causes stupor, coma, or convulsions

(Definition from merriam-webster.com)

  • narcotic would not apply in this case, although narcotics do induce sleep sometimes, they are more to be used as extreme pain killers.
    – tox123
    Commented Nov 30, 2014 at 23:48
  • @x-x - Agreed, it's not the go-to choice, for the reason you stated; I included it here for the sake of completeness.
    – Erik Kowal
    Commented Nov 30, 2014 at 23:59
  • also for the sake of completeness: thefreedictionary.com/hypnotic
    – Anentropic
    Commented Dec 1, 2014 at 0:18
  • 3
    @x-x the fact that the word "narcotic" refers to a class of drugs which are primarily employed today as pain killers does not at all obviate the fact that the older meaning of the adjective "narcotic" -- after which that class of drugs was (perhaps mistakenly) named -- is, quite literally, "sleep-inducing". From the Greek root 'narkóō'. Commented Dec 1, 2014 at 21:00
  • @Codeswitcher I was not aware of the roots, only of the current use of the word.
    – tox123
    Commented Dec 2, 2014 at 0:29

If you want a modern, neologian spin, I'd invent with "hybernetic" or "torporant" ...

"He imbibed a noxious hybernetic and could nigh be shocked to for days."

"The liquor, a decided torporant, reduced him to felinity within minutes."

~ me

PS — these ain't in the dictionary... not yet anyway. But what is English if not a neologian's frolickeria?

  • 1
    Neologician or novovocabulist? Commented Feb 5, 2015 at 3:43

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