妹妹
younger sister
mèimei
What does 妹妹 mean?
妹妹 (mèimei) means 'younger sister.' Chinese kinship terms encode age relative to the speaker, so there is no general word for 'sister' — you must specify 妹妹 (younger) or 姐姐 (jiějie, older). The second syllable is a neutral tone (mèimei, not mèimèi), which is typical of family terms (爸爸, 妈妈, 哥哥). Possession usually drops the 的 particle for close family: 我妹妹 ('my younger sister'), 他妹妹 ('his younger sister'). 妹妹 is also used informally to address or refer to a young girl who is not actually one's sister — for example, a stranger calling out to a younger woman in a friendly way (小妹妹 'little girl,' 美女妹妹 in playful contexts). The single-character form 妹 (mèi) appears in compounds like 姐妹 (jiěmèi, 'sisters') and 表妹 (biǎomèi, 'younger female cousin').
Note: 妹妹 is the everyday word for one's younger sister. The second syllable is neutral tone (mèimei). Older sister is 姐姐 (jiějie) — Chinese kinship terms always specify whether the sibling is older or younger.
Character breakdown
younger sister (女 'female' radical + 未 'not yet' phonetic — the 'not yet grown' female)
repeated for the disyllabic kinship term; second syllable is neutral tone
Memory hook: 女 (female) + 未 ('not yet') — the 'not yet [grown]' female = younger sister.
Measure word for 妹妹
Example sentences
我有一个妹妹。
Wǒ yǒu yí ge mèimei.
I have a younger sister.
spoken
我妹妹今年十岁。
Wǒ mèimei jīnnián shí suì.
My younger sister is ten this year.
spoken
妹妹喜欢喝牛奶。
Mèimei xǐhuan hē niúnǎi.
My younger sister likes drinking milk.
spoken
她的妹妹很漂亮。
Tā de mèimei hěn piàoliang.
Her younger sister is very pretty.
spoken
姐姐和妹妹一起去学校。
Jiějie hé mèimei yìqǐ qù xuéxiào.
Older sister and younger sister go to school together.
neutral
Common phrases with 妹妹
Synonyms
妹 alone is the single-character form, used in compounds (姐妹 'sisters,' 表妹 'younger female cousin') or as a direct address. 妹妹 is the standard noun form for reference and address.
小妹 ('little sister') is an affectionate or familial nickname, also used to address a young woman politely in service contexts (waitress, shop). 妹妹 is the neutral standard term.
Don't confuse 妹妹 with
姐姐 is 'older sister.' Chinese always distinguishes age: 妹妹 = younger, 姐姐 = older. There's no neutral 'sister.'
弟弟 is 'younger brother' — the male equivalent of 妹妹. Same age relation (younger), different gender.
美 (měi) means 'beautiful' and looks somewhat similar in handwriting. Different pronunciation (měi vs mèi) and different meaning.