Where does “vagellaio” come from?

vagellaio (Italian) comes from Italian -aio, from Latin -ārius, from Proto-Italic *-āzios — Forms relational adjectives to nouns (and rarely numerals).

Ancestry of “vagellaio”, step by step

Step	Language	Word	Meaning
1	Italian	-aio	Added to nouns to form agent nouns; Added to...
2	Latin	-ārius	er
3	Proto-Italic	*-āzios	Forms relational adjectives to nouns (and rarely numerals)

Every word from Proto-Italic *-āzios →Every word from Latin -ārius →Every word from Italian -aio →