espouser
/ˈɛspuːzeɪ, ˈɛspuːzər/Definitions
1. verb
to take or have as one’s spouse, especially in a formal or official sense
“The couple decided to espouse each other in a lavish wedding ceremony.”
2. noun
a person who has taken or has a spouse, especially in a formal or official sense
“The espouser of the young woman was a wealthy businessman.”