Where does “sleeping power” come from?

sleeping power (English) comes from English Power, from Middle English power, from Anglo-Norman poer, from Latin potēre, from Latin posse, from Latin potis, from Proto-Italic potis, from Proto-Indo-European pótis — to drink.

sleeping power (English): A power which is unused, or which has not been exercised for a long time; especially one which is extensive, but little-known

Definitions

  1. A power which is unused, or which has not been exercised for a long time; especially one which is extensive, but little-known

Ancestry of “sleeping power”, step by step

sleeping power traces back through two separate lines of ancestry.

via English Power

StepLanguageWordMeaning
1EnglishPowerA button of a computer, a video game console, or...
2Middle EnglishpowerAbility, power or capability
3Anglo-Normanpoer
4Latinpotēre
5Latinpossepresent active infinitive of possum  "to be able...
6Latinpotisable, capable, possible
7Proto-Italicpotismaster, in control of
8Proto-Indo-Europeanpótismaster, ruler; husband
9Proto-Indo-Europeanph₃tis
10Proto-Indo-Europeanpeh₃-to drink

via English sleeping

StepLanguageWordMeaning
1Englishsleepingpresent participle of sleep; Asleep; Used for...
2EnglishsleepTo rest in a state of reduced consciousness; To...
3Middle Englishslepento sleep; to become asleep, to cause to sleep; to...
4Old Englishslǣpan
5Proto-West Germanicslāpanto sleep
6Proto-Germanicslēpanąto sleep
7Proto-Indo-Europeanslab-to be weak, be languid; be weak, limp, languid
Every word from Proto-Indo-European peh₃-