She had been 'betrothed' to the prince since she was a young girl.
He spent the afternoon with his 'betrothed'. [='fiancée']
a 'betrothed' couple
(..) Wow! Shhh! Zazu. Right. So how are we gonna ditch the dodo? Oh I know how we can-- Oh, just look at you two. Little seeds of romance blossoming in the savannah. Your parents will be thrilled... what with your being betrothed and all. Be-what? Betrothed. Intended. Affianced. Meaning...? Yuck! Ewww! (..)1994 The Lion King