Where does “odōs” come from?

odōs (Proto-Italic) comes from Proto-Indo-European h₃édos, from Proto-Indo-European h₃ed- — to smell, stink; to hate; to bite.

Ancestry of “odōs”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	h₃édos	—
2	Proto-Indo-European	h₃ed-	to smell, stink; to hate; to bite

odōs — Etymology, Origin & Word History | Etymology Explorer