Second-Hand Mayonnaise
Excess mayonnaise that has been wiped from a butter knife to the edge of the mayonnaise jar.
"I can't reach the bottom of this jar, but the second-hand mayonnaise at the top has bread crumbs in it."
Mayonnaise Hands
After you eat a jar of mayonnaise with your bare hands and your hands are sticky and it looks and feels like you came on your hands.
Brad: Yo I shook Chad's hand and it felt like there was cum on it
Jacob: No I think he just has mayonnaise hands.
Jacob: No I think he just has mayonnaise hands.