Where does “achromatopsja” come from?

achromatopsja (Polish) comes from Polish a-, from Ancient Greek ἀ-, from Proto-Hellenic hə-, from Proto-Indo-European sm̥-, from Proto-Indo-European sem- — together, one.

Ancestry of “achromatopsja”, step by step

Step	Language	Word	Meaning
1	Polish	a-	forming words with the sense of negation
2	Ancient Greek	ἀ-	The alpha privativum, used to make words that...
3	Proto-Hellenic	hə-	same; together
4	Proto-Indo-European	sm̥-	one; with, together
5	Proto-Indo-European	sem-	together, one

Every word from Proto-Indo-European sem- →Every word from Ancient Greek ἀ- →Every word from Proto-Indo-European sm̥- →