Where does “nonunderground” come from?

nonunderground (English) comes from English non, from French non, from Old French non, from Latin nōn, from Old Latin noenum, from Proto-Indo-European óynos — one; single.

nonunderground (English): Not underground (hidden or secretive); overt, public, mainstream

Definitions

  1. Not underground (hidden or secretive); overt, public, mainstream

Ancestry of “nonunderground”, step by step

nonunderground traces back through two separate lines of ancestry.

via English non

StepLanguageWordMeaning
1EnglishnonObsolete form of none
2Frenchnonno; not; a no, a negative response
3Old Frenchnonno; not; Alternative form of nom
4Latinnōnnot
5Old Latinnoenum—
6Proto-Indo-Europeanóynosone; single

via English underground

StepLanguageWordMeaning
1EnglishundergroundBelow the ground; below the surface of the Earth;...
2Middle Englishundergrounde—
Every word from Proto-Indo-European óynos →Every word from Old Latin noenum →Every word from Latin nōn →