1. 婚约：betroth 许配 | betrothal 婚约 | betrothed 已订婚者

2. 订婚：兽性,人兽相交 Bestiality | 订婚 Betrothal | 偏见,蔽 Bias

3. 婚约, 订婚礼：betroth || 许配 | betrothal || 婚约, 订婚礼 | betrothed || 已订婚者 订婚了的

4. 订婚礼：订婚戒指band ; engagement ring | 订婚礼betrothal | 恩爱夫妻affectionate couple

1. 婚约；订婚
A betrothal is an agreement to be married.

noun

1. the act of becoming betrothed or engaged

Synonym: espousal

2. a mutual promise to marry

Synonym: trothengagement