betroth
Concise Oxford English Dictionary © 2008 Oxford University Press:
betroth /bɪˈtrəʊð, -θ/
▶verb (be betrothed) dated be formally engaged to be married. ▶noun (one's betrothed) the person to whom one is engaged.
– derivatives
betrothal noun.
betrothal noun.
'betroth' also found in these Oxford entries:

