Where does “parasitus” come from?

parasitus (Latin) comes from Ancient Greek παράσιτος, from Ancient Greek παρά, from Latin verēdus, from Gaulish werēdos, from Proto-Celtic *uɸoreidos.

Ancestry of “parasitus”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	παράσιτος	one who eats at the table of another, parasite;...
2	Ancient Greek	παρά
3	Latin	verēdus	—
4	Gaulish	werēdos	horse
5	Proto-Celtic	*uɸoreidos	—

Every word from Proto-Celtic *uɸoreidos →

parasitus — Etymology, Origin & Word History | Etymology Explorer