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child (esp. a boy)
viscount
founder of a school of thought (esp. Confucius); master
-er (i.e. man who spends all his time doing ...)
masters and philosophers (categorization of Chinese classical literature)
counter for played stones
「子」 has other readings with different meanings.
太郎は元気な子に育った。
Taro grew up to be an energetic child.
孔子は古代中国の思想家だ。
Confucius is a thinker from ancient China.
利子を計算してみた。
I tried calculating the interest.