Where does “Eukaryota” come from?

Eukaryota (Translingual) comes from Ancient Greek κάρυον, from Proto-Indo-European ḱerh₂- — head, top; horn.

Ancestry of “Eukaryota”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	κάρυον	nut
2	Proto-Indo-European	ḱerh₂-	head, top; horn