The term has been used as a code when a hot girl is near to avoid her suspicion while you talk about her. It is implied that you are talking about her, but she just thinks you're talking about someone's mom.
*girl is near*
Joey: Did you see 'Nate's Mom'?
Christian: yea, she is so hot, dude!
Nate's mom is a MILF. She's even hotter than Stacey's mom. 10/10 would bang.
Person 1: Why did you go to Nate's house? I didn't think you liked him.
Person 2: I don't, I came to see Nate's mom.
Nate does not have a father. He has two mothers. no father. just a couple mothers. no dad. his dad is non-existent when I bring up my dad, Nate gets depressed. sorry Nate, but you have no dad.
English teacher: where did everyone get their Hawaiian shirts for spirit week
ALMOST entire class- my dad gave it to me
Nate- *looks down at nike shirt crying*
Noah- Wearing same sweatshirt again. I like Nate's momS.