significant other

US /sɪɡˈnɪf.ɪ.kənt ˈʌð.ər/
UK /sɪɡˈnɪf.ɪ.kənt ˈʌð.ər/
"significant other" picture
1.

partner, dolce metà

a person with whom someone has a long-term, committed relationship, especially one who is not a spouse but is considered a partner in life

:
She introduced him to her significant other at the party.
Lo ha presentato al suo partner alla festa.
Many people prefer to use 'significant other' instead of 'boyfriend' or 'girlfriend' to be more inclusive.
Molte persone preferiscono usare 'partner' invece di 'fidanzato' o 'fidanzata' per essere più inclusivi.