The Spiderweb is achieved through male masturbation in the shower, typically done with the aid of a soapy substance. After ejaculation, as the male lifts his hand up and spreads his fingers apart, it looks like a spiderweb. May also be flung at or on partner after said ejaculation in conjunction with the male shouting "Spiderweb!" and mimicking the motion of Spiderman shooting his spiderweb in the popular comic books and movies.
I'm sorry I just Spiderwebbed you in the face, neck, shoulders, chest, and stomach.
A spider web is when you fart and touching two distant objects with your butt, creating a gas cloud that others have to walk through. For example, standing in the door and farting, touching your butt to both door jambs, and yelling, "spider web!"
Everyone was in the room when I felt a big one coming on....I totally let it rip and touched my ass to the tables...creating a big spider web that everyone had to walk through!