姻 (yīn) — (bound form) marriage; related by marriage

Definition

姻 is a bound morpheme meaning 'marriage' or 'related by marriage' — it never stands alone, always attached to a partner word like 姻亲 or 婚姻.

bound form

(bound form) marriagerelated by marriage

。
Tā men de hūn yīn hěn xìng fú.
Their marriage is very happy.
。
Tā men liǎng jiā shì yīn qīn.
The two families are related by marriage.
。
Zhè cì lián yīn jiā qiáng le liǎng guó de guān xì.
This marriage alliance strengthened the relationship between the two countries.