Boosie Badazz says Diddy should've held it together after he was found guilty in his federal trial ... tearing into the dude for not being manly enough when the verdict came down.

The rapper sat down for an interview on "The Breastfast Club" Friday ... and, he talked about his relationship to the disgraced music mogul -- revealing the two haven't spoke in a long time despite their friendly relationship in the past. Gallery Launch Gallery Getty

Boosie says he wants to talk to the guy though ... because he thinks it was a total coward move to cry after the jury read out the verdict in his federal sex trafficking case.

Listen to the audio yourself -- we certainly can't quote much from it given the colorful langauge -- but it basically sounds like Boosie expected Diddy

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