(one's) better half
One's spouse or romantic partner. I'd love to come out with you guys after work, but I'd better check in with my better half to make sure we don't have any plans for this evening. The work retreat is meant to be for couples, so be sure to bring your better half!
your better half
your husband or wife. humorousyour better/other ˈhalf
(informal, humorous) your wife or husband: I’ll have to ask my better half about that.