Where does “fótachlaonmhéadar” come from?

fótachlaonmhéadar (Irish) comes from Irish fóta-, from Ancient Greek φῶς, from Proto-Hellenic pʰáos, from Proto-Indo-European bʰéh₂os, from Proto-Indo-European bʰeh₂-, from Proto-Indo-European bʰeh₂-s-ri-.

fótachlaonmhéadar (Irish): photoclinometer

Definitions

photoclinometer

Ancestry of “fótachlaonmhéadar”, step by step

Step	Language	Word	Meaning
1	Irish	fóta-	photo-
2	Ancient Greek	φῶς	Attic form of φᾰ́ος
3	Proto-Hellenic	pʰáos	—
4	Proto-Indo-European	bʰéh₂os	—
5	Proto-Indo-European	bʰeh₂-	to shine, glow light; to speak, say
6	Proto-Indo-European	bʰeh₂-s-ri-	—

Every word from Proto-Indo-European bʰeh₂-s-ri- →Every word from Proto-Indo-European bʰeh₂- →Every word from Proto-Indo-European bʰéh₂os →