Deliberate or ironic misspelling of "poster," meaning a twitter user. Noun.
Alternative forms of the word include poast (n) – a misspelling of "post", referring to tweets.

It can be appended as a suffix behind other words, such as shitpoaster (n) or shitpoasting (v).
Trump was irritating, sure, but you can't deny he was perhaps this hellsite's greatest poaster
by joy8374(2 April 24, 2021
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ur info if all newbie pasted info poazing (posing)
Stop that poaster spamming his google + yandex bs.. its cyber generated
by skullsfireNdieneverdie February 6, 2020
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