Where does “all clear” come from?

all clear (English) comes from English all, from Middle English all, from Old English eall, from Proto-West Germanic all, from Proto-Germanic allaz, from Proto-Indo-European h₂él- — to grow, nourish.

all clear (English): a signal that danger, such as an air raid, is...

Definitions

  1. a signal that danger, such as an air raid, is...

Ancestry of “all clear”, step by step

all clear traces back through two separate lines of ancestry.

via English all

StepLanguageWordMeaning
1EnglishallEvery individual or anything of the given class,...
2Middle Englishallall; all, every
3Old Englisheallall; whole, entire; everything
4Proto-West Germanicallall
5Proto-Germanicallazall
6Proto-Indo-Europeanh₂él-to grow, nourish

via English Clear

StepLanguageWordMeaning
1EnglishClearAn idea state of beingness free of unwanted...
2Middle EnglishclereAlternative spelling of cler
3Old Frenchclerbright, well-lit, not dark; clear
4Latinclārusclear, bright
5Proto-Indo-Europeanḱelh₁-to warm up, to be hot; to warm up, be hot
Every word from Proto-Indo-European h₂él- →Every word from Proto-Germanic allaz →Every word from Proto-West Germanic all →