Merwin \m(e)-rwin, mer-win\ as a boy's name is a variant of Marvin (Welsh) and Mervin (Old Welsh), and the meaning of Merwin is "sea friend".

The baby name Merwin sounds like Merwyn, Marwin and Merwinn. Other similar baby names are Berwin, Derwin, Kerwin, Medwin, Melwin and Merlin.