When a large sum of people from a group or multiple groups start flooding into a website or online community. Often normies, but sometimes other groups. This may be good or bad usually bad. May or may not permanently effect the website/community.
Facebook is immune to webvasion, as it's already full of normies.
4chan is also immune, as the current community is so disgusting most people leave immediately.
Youtube's already been webvaded.
by Joe The Autistic February 12, 2016
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