girlfriend / fiancée
fidanzate
fee-dan-DZAH-tah
Like fidanzato, fidanzata can mean both 'girlfriend' (in a relationship) and 'fiancée' (engaged). In formal Italian, 'promessa sposa' is used for a fiancée, but this is rare in modern speech.
Ti presento la mia fidanzata, Sara.
Let me introduce my girlfriend, Sara.
La mia fidanzata viene da Napoli.
My girlfriend is from Naples.