1 (wiktionary) 2 (vi.wikipedia) 3 (en.wikipedia) 4 (glosbe)

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ETYMOLOGY

HAN VIET: muội muội 妹妹

KOREAN 3.0	Eng	Wordtype	Etym.	Gb	Vie
☆☆☆	YOUNGER SISTER	Noun	女 동생	妹妹	em gái
☆☆☆	BROTHER; SISTER	Noun		弟弟；妹妹	em