Where does “鈴木” come from?

鈴木 (Japanese) comes from Japanese 木, from Old Japanese 木, from Proto-Japonic kəy — tree.

Ancestry of “鈴木”, step by step

Step	Language	Word	Meaning
1	Japanese	木	a tree or shrub; wood, timber, lumber; a tree
2	Old Japanese	木	a tree or shrub; wood, timber, lumber; Combining...
3	Proto-Japonic	kəy	tree

鈴木 — Etymology, Origin & Word History | Etymology Explorer