Where does “caliginosus” come from?

caliginosus (Latin) comes from Latin -ōsus, from Old Latin -ōssus.

Ancestry of “caliginosus”, step by step

Step	Language	Word	Meaning
1	Latin	-ōsus	—
2	Old Latin	-ōssus	—

caliginosus — Etymology, Origin & Word History | Etymology Explorer