Where does “luggo-” come from?

luggo- (Proto-Celtic) comes from Proto-Indo-European lewǵ- — to break, tear; to break, shatter.

Ancestry of “luggo-”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	lewǵ-	to break, tear; to break, shatter

luggo- — Etymology, Origin & Word History | Etymology Explorer