While it's true that "mama" means mother, men often say it as a term of endearment towards a woman. This is particularly true in western pop/R&B music and pop culture. Unless the song specifically refers to the person in a motherly way, it most likely means their girlfriend or a girl they are interested in romantically.

''mama'' means mother.

the ways say mother in english - mom, momma, mommy, ma, mamma, mummy, mammy, mum, mama

momma is like saying sweet heart or honey, but is not as sweet.

i think it's 妈妈, 美国人也是这样说的. But not sure.. =) hehe..