Where does “mountdown” come from?

mountdown (English) comes from English Down, from Middle English doun, from Old English dūn, from Proto-Germanic *dūnā, from Proto-Celtic dūnom, from Proto-Indo-European dʰewh₂- — smoke; mist, haze.

mountdown (English): The act of mounting an electrical component onto...

Definitions

  1. The act of mounting an electrical component onto...

Ancestry of “mountdown”, step by step

mountdown traces back through two separate lines of ancestry.

via English Down

StepLanguageWordMeaning
1EnglishDownusually known as County Down
2Middle Englishdoundown
3Old Englishdūnhill, down; hill, dune; hill, mountain
4Proto-Germanic*dūnā
5Proto-Celticdūnomstronghold, rampart
6Proto-Indo-Europeandʰewh₂-smoke; mist, haze

via English Mount

StepLanguageWordMeaning
1EnglishMountOS grid ref SW7856
2Middle EnglishmountA mountain; a mount or peak, especially the Alps
3Old Englishmunta hill, mound; a mount or mountain
4Latinmōnsmountain, mount
5Proto-Italic*monts
6Proto-Indo-Europeanmen-to think, mind; spiritual activity; to stay,...
Every word from Proto-Indo-European dʰewh₂-Every word from Proto-Celtic dūnomEvery word from Proto-Germanic *dūnā