mi reina

Spanish Terms of Endearment for Female Lover

means “my queen”

This is pretty straightforward. It could be used by a husband for his wife, but also by a waitress for a patron or when you hold someone in high regard.

Mi reina, ¿qué quieres tomar? – My queen, what do you want to drink?
Cómo estás mi reina, tiempo sin verte – How are you my queen, long time no see.
Le daré una sorpresa de cumpleaños a mi reina – I will give my queen a birthday surprise.