The practice of using commas and other punctuation marks incorrectly. The writer is usually aware that a comma is needed in the sentence they're writing, but is unclear as to when and where it should be placed. The amount of commas then used is so absurd that it would appear they had figuratively 'vomited' commas all over the piece they have written.
Email from Mark:

'Michelle, did you, want to go to, the park, and have a picnic, and maybe, let me, play with, your boobs, for a bit.'

Email reply from Michelle

'Mark, you're vomiting commas again. You're not getting anywhere near my tits until you stop being a fuckwit and learn some basic grammar'
by tincopper July 13, 2016
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