Nikki Minaj certainly speaks some Spanish, although it does not appear that she is fluent. She can definitely roll off the alphabet pretty swiftly though (see video)
During an interview on Lopez Tonight at the end of 2010, she invented an alter ego she calls Rosa (pronounced "Rrrrrrrrosaaaa") for the host George Lopez, who is Mexican. Rosa resurfaced again on the Chelsea Lately show.
She also sang in Spanish for a verse on the Romeo Santos song "Animales" :
"Romeo...
It's me, yo, the CEO
Dame beso, yo necesito
Dominicana, Puerto Rico
Fly me out where is warm, hace frío
And you can hit it like José Canseco
Yeah, I'm-a give you this hit; caliente
But I'mma need a big sweet Presidente
Baby, you like it rough?
Give it to me toda la noche
Por favor, baby, rip me right out of my Dolce
Gabbana, como animales
Baby, como animales"
