Where does “Seaman” come from?

Seaman comes from Middle English seman, from Old English sǣmann, a compound of sǣ (sea) and mann (man).

Ancestry of “Seaman”, step by step

Step	Language	Word	Meaning
1	Middle Dutch	seeman	—
2	Old English	sǣmann	seaman

Seaman — Etymology, Origin & Word History | Etymology Explorer