郎
ロウ, リョウ, おとこ, いら, お, とう, もん, ろ, ろお

son, counter for sons

JLPT1 G7 S9 F569

As per 良# (flowing stream) + 邑 village/settlement → village/settlement adjacent to a pure, flowing stream. Via "pure," 郎 came to indicate a "clean/pure young man," next became a term by which wives addressed their husbands, and finally developed into a euphemism for a male → *man*.

[Full Kanji Etymology List]