sleep
A natural state of rest in which consciousness is suspended.
Etymology
From Old English slǣpan, from Proto-Germanic *slēpaną — the deeper PIE etymology is uncertain, though it may be related to a root meaning "to be slack, limp." The PIE word for sleep is *swépnos, which gives English "somnolent," "insomnia" (via Latin somnus), and "hypnosis" (via Greek hýpnos) — but not English "sleep" itself, which is a Germanic word of obscure origin.
The Journey: (uncertain) → sleep
*swépnos
somnus
hýpnos
insomnia, hypnosis
Cognates Across Languages
These words in other languages descend from the same PIE root (uncertain). They are not borrowings but independent inheritances from a common ancestor.
| Language | Word |
|---|---|
| Greek | hýpnos |
| Latin | somnus |
| Welsh | hun |
| Armenian | kʿun |
| Sanskrit | svápna |
| Old Irish | suan |
| Lithuanian | sapnas |
| Old Church Slavonic | sŭnŭ |
Did You Know?
Hypnosis and insomnia both descend from PIE *swépnos "sleep" — but English "sleep" itself does not. Greek hýpnos "sleep" gave us "hypnosis" (coined 1843), while Latin somnus "sleep" gave us "insomnia." The native English word "sleep" has a different, obscure origin.