baby mama

slang The birth mother of one's child or children, especially when she is not one's wife. Sometime hyphenated or spelled as one word. You may not be in a serious relationship, but she's your baby mama, Jack—she's going to be a part of your life forever now! It was weird at first having the kids' baby mama around so much, but I'm glad that she gets to remain so involved with their lives. No, Trudy is Justin's baby mama. They're not married.