Lewin is a male name.
Lewin is a form of Levin. It is for example a Low German or Dutch form of the Old Germanic name Liebwin or Lebuin or Liafwin. Lewin derived as well from the Hebrew name Levi and is a Yiddish diminutive of Lion. Some people say Lewin is of Arabic origin.
Lewin means “dear/beloved friend” (from Germanic “liob/liub” = dear/beloved + “wini” = friend), “attached”, “joined” (from Levi), “colour”, “character” (in Arabic).