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弟弟
dìdi
younger brother
弟弟喜欢玩电脑游戏。
My younger brother likes playing computer games.
informal
A male sibling younger than oneself.
我有两个弟弟。
I have two younger brothers.
弟弟比我小三岁。
My younger brother is three years younger than me.
Used regardless of age difference if both parties are male siblings. In formal contexts, '弟' (dì) alone may be used.
Pro Tip
Distinguishing '弟弟' from '哥哥'
Use '弟弟' for younger brothers and '哥哥' for elder brothers. Age order is relative to the speaker, not absolute.
Gold Rule
Gender and Age Rule
Only use '弟弟' for male siblings younger than the speaker. For female siblings, use '妹妹'.
Word Origin
From Middle Chinese 'diej' (弟) + diminutive suffix 'di' (弟), referring to a younger male sibling. The reduplication emphasizes affection or familiarity.
Usage Notes
Commonly used in everyday speech. In writing, '弟' alone suffices, but '弟弟' is more affectionate or colloquial. In formal contexts like family trees, '弟' is preferred.
Word Breakdown
弟
younger brother
root弟
diminutive suffix (repetition for affection)
suffix汉英词典