A sock that is used on multiple occasions to jerk off inside of. It becomes stiff around the toe area that catches the brunt of the loads.
ME: Dude I think Mom found my Steel-toe sock under my bed.
DAD: She did. When I tried to tell her to leave it there so you didn't ruin another one she threatened to put it on and kick me with it
ME: she should've
Someone who has really small boobs, and doesn't wear a bra, so it looks like they would fit into a sock. The "toe" part is the nipple that sticks out of the "sock" and shows through the shirt.
Martha has some real Toe Sock Tits, and they're nasty!! You can see right through her shirt.