Where does “Ruderer” come from?

Ruderer (German) comes from German -er, from Old High German -āri, from Proto-West Germanic -ārī, from Proto-Germanic -ārijaz, from Latin -ārius, from Proto-Italic *-āzios — Forms relational adjectives to nouns (and rarely numerals).

Ruderer (German): agent noun of rudern; oarsman; rower; canoeist;...

Definitions

agent noun of rudern; oarsman; rower; canoeist;...

Ancestry of “Ruderer”, step by step

Step	Language	Word	Meaning
1	German	-er	Forms agent nouns etc. from verbs, suffixed to...
2	Old High German	-āri	used to form agent nouns
3	Proto-West Germanic	-ārī	-er
4	Proto-Germanic	-ārijaz	-er
5	Latin	-ārius	er
6	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 German -er →