Where does “Ectognatha” come from?

Ectognatha (Translingual) comes from Ancient Greek ἐκτός, from Ancient Greek γνάθος, from Proto-Indo-European ǵn̥h₂dʰ-os, from Proto-Indo-European ǵneh₂dʰ-.

Ancestry of “Ectognatha”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	ἐκτός	without, outside, out; external, strange, vulgar;...
2	Ancient Greek	γνάθος	jaw; point, edge; type of stone
3	Proto-Indo-European	ǵn̥h₂dʰ-os	—
4	Proto-Indo-European	ǵneh₂dʰ-	—

Every word from Proto-Indo-European ǵneh₂dʰ- →Every word from Proto-Indo-European ǵn̥h₂dʰ-os →Every word from Ancient Greek γνάθος →