Where does “midair” come from?

Midair derives from air, which comes from Middle English air, Anglo-Norman eir, Latin āēr meaning air or atmosphere, ultimately from Proto-Indo-European ǵʰeh₁ro-.

midair (English): In the act of flight; airborne; a collision...

Definitions

  1. In the act of flight; airborne; a collision...

Ancestry of “midair”, step by step

midair traces back through two separate lines of ancestry.

via English MID

StepLanguageWordMeaning
1EnglishMIDInitialism of mobile information device
2Englishmid-rangeOf a central or halfway point
3EnglishrangeA line or series of mountains, buildings, etc; A...
4Middle Englishrengen
5Old Frenchrengierto line up; to form ranks
6Old Frenchrengplace; position
7Latinrencusrow; order, rank
8Gaulishrekos
9Proto-Celticreketito arrange
10Proto-Indo-European(H)rek-to set in order

via English aïr

StepLanguageWordMeaning
1Englishaïr
2Middle Englishaireair
3Old Frenchairair mixture of gases that make up the earth's atmosphere
4Latināērair
5Ancient Greekἀήρmist; air; wind
6Ancient Greekauhḗr
Every word from Proto-Indo-European (H)rek-