Noun - The mix of vomit and sperm that results when one gags on a deep-throated wang at the exact moment it shoots its load, causing you throw up all over the offending cock and balls.
Ex. 1 - Ben was trying to reenact a scene from "Throat Chokers 4" with his girlfriend and she ended up spewing sneath all over him.
Ex. 2 - Maybe there's something wrong with me, but nothing beats warm sneath in the morning.