steady
n. countable B2 Upper Intermediate Oxford US //ˈstɛdi// UK //stˈɛdi// steady
n. a person you date regularly and have a serious relationship with. It is an older, casual way to talk about a boyfriend or girlfriend.
n. a person with whom one has a regular and exclusive romantic relationship. Informal in register and somewhat dated in modern usage.
She brought her new steady to the family dinner.
In the mid-20th century, it was common for teenagers to give their class ring to their steady as a sign of commitment.
While the term has largely been replaced by more modern labels, it still evokes a specific era of courtship where having a steady implied a clear social contract.
Usage
Typically used with a possessive pronoun like 'my' or 'her'.