Where does “echtra” come from?

echtra (Old Irish) comes from Old Irish echtar, from Proto-Celtic *exteros, from Proto-Indo-European h₁eǵʰs — out.

Ancestry of “echtra”, step by step

StepLanguageWordMeaning
1Old Irishechtarwithout, outside
2Proto-Celtic*exterosoutside
3Proto-Indo-Europeanh₁eǵʰsout

Words derived from “echtra”

Every word from Proto-Indo-European h₁eǵʰs →Every word from Proto-Celtic *exteros →Every word from Old Irish echtar →
echtra — Etymology, Origin & Word History | Etymology Explorer