think of the word "berate" (to scold/rebuke)--- vitu(p)BERATE
vituperate: vittu(a guy) pe rage...to use harsh condemnatory language to abuse..
vituperate. sounds like vethu po+rate i.e to rate someone negatively and condemn/criticise them
vit sound like fit of perate(parade)
Imagine a *bitter(vitu)* + *parade*(perate), where one angrily blame each other or insults each other.