sleep

Etymology 1

From Middle English slepen, from Anglian Old English slēpan, a variant of slǣpan, from Proto-West Germanic *slāpan, from Proto-Germanic *slēpaną.

verb

1. (intransitive) To rest in a state of reduced consciousness.
   You should sleep eight hours a day.
   We sleep in the bedroom. Audio (US) (file) 2016, VOA Learning English (public domain)
2. (transitive) To be slumbering in (a state).
   to sleep a dreamless sleep
3. (transitive, reflexive) To achieve or make happen by manner of sleep.
   Sleep your way to good health.
   He hoped to sleep his troubles away.
4. (idiomatic, euphemistic) To have sexual intercourse (see sleep with).
   Last night we slept together for the first time.
   1. (idiomatic) To earn by sexual favors.
      Oh, she didnt earn her promotion, she just slept her way to the top.
5. (transitive) To accommodate in beds.
   This caravan can sleep four people comfortably.
6. (intransitive) To be careless, inattentive, or unconcerned; not to be vigilant; to live thoughtlessly.
7. (intransitive) To be dead; to lie in the grave.
8. (intransitive) To be, or appear to be, in repose; to be quiet; to be unemployed, unused, or unagitated; to rest; to lie dormant.
   a question sleeps for the present; the law sleeps
9. (computing, intransitive) To wait for a period of time without performing any action.
   After a failed connection attempt, the program sleeps for 5 seconds before trying again.
10. (computing, transitive) To place into a state of hibernation.
    Even when you have reasons not to sleep the computer, it's still a good idea to sleep the display after a period of time. 2009, Mike Lee, Scott Meyers, Learn Mac OS X Snow Leopard, page 91
11. (intransitive, mechanics, dynamics) To spin on its axis with no other perceptible motion.
    When a top is sleeping, it is spinning but not precessing.
    A top sleeps when it moves with such velocity, and spins so smoothly, that its motion is imperceptible. 1854, Anne E. Baker, Glossary of Northamptonshire Words and Phrases
12. (transitive, mechanics, dynamics) To cause (a spinning top or yo-yo) to spin on its axis with no other perceptible motion.
    Yo-yo tricks involving sleeping the yo-yo (like "walking the dog" and "rocking the baby") cannot be performed in space. 1995, All Aboard for Space: Introducing Space to Youngsters, page 158

Etymology 2

From Middle English slepe, sleep, sleepe, from Old English slǣp (“sleep”), from Proto-West Germanic *slāp, from Proto-Germanic *slēpaz (“sleep”).

noun

1. (uncountable) The state of reduced consciousness during which a human or animal rests in a daily rhythm.
   I really need some sleep.
   We need to conduct an overnight sleep test to diagnose your sleep problem.
2. (countable, informal) An act or instance of sleeping.
   I’m just going to have a quick sleep.
3. (informal, metonymically) A night.
   There are only three sleeps till Christmas!
4. (uncountable) Rheum, crusty or gummy discharge found in the corner of the eyes after waking, whether real or a figurative objectification of sleep (in the sense of reduced consciousness).
   Wipe the sleep from your eyes.
   When she had rubbed the sleep out of her eyes and wept till she was tired, she set out on her way and walked for many, many a day, till she at last came to a big mountain. 1886, Peter Christen Asbjørnsen, translated by H.L. Brækstad, Folk and Fairy Tales, page 233
   … and draw the medial canthus (aka medial commissure) at the medial extreme. Now draw the lacrimal caruncle at the medial corner of the eye, which produces whitish, oily fluid—it produces “sleep in the eye.” 2017, Adam J. Fisch, Neuroanatomy: Draw It to Know It, Oxford University Press
   The part of the eyelid that is the location of the lacrimal caruncle, which produces rheum or "sleep," the gritty substance often present when awakening. 2019, Jahangir Moini, Anatomy and Physiology for Health Professionals, Jones & Bartlett Learning, page 780, entry "Medial canthus"
5. A state of plants, usually at night, when their leaflets approach each other and the flowers close and droop, or are covered by the folded leaves.
   The daily sleep of plants, and their winter sleep, present in this respect exactly similar phenomena[…] 1843, Joh Müller, John Bell, Elements of Physiology, page 808
6. The hibernation of animals.