Where does “ictiose” come from?

ictiose (Portuguese) comes from Portuguese ictio-, from Ancient Greek ἰχθύς, from Ancient Greek ἀετός, from Proto-Hellenic ayyetós, from Proto-Indo-European h₂ewyetós, from Proto-Indo-European h₂éwis — bird.

ictiose (Portuguese): ichthyosis

Definitions

ichthyosis

Ancestry of “ictiose”, step by step

Step	Language	Word	Meaning
1	Portuguese	ictio-	ichthyo-
2	Ancient Greek	ἰχθύς	fish
3	Ancient Greek	ἀετός	eagle; the constellation Aquila; omen
4	Proto-Hellenic	ayyetós	—
5	Proto-Indo-European	h₂ewyetós	—
6	Proto-Indo-European	h₂éwis	bird

Every word from Proto-Indo-European h₂éwis →Every word from Proto-Indo-European h₂ewyetós →Every word from Proto-Hellenic ayyetós →