betrothal

名词 betrothal:

1. a mutual promise to marry
   同义词：troth, engagement
2. the act of becoming betrothed or engaged
   同义词：espousal

be.troth.al

n.（名词）
The act of betrothing or the fact of being betrothed.
订婚：订婚的行为或已订婚的事实
A mutual promise to marry; an engagement:
婚约：对结婚的相互许诺；婚约：
例句：
announced their betrothal the next day.
宣布他们明天订婚