When someone says something iconic or amazing, either them or someone else would say "periodt" to finish the conversation as if they just won the "disagreement".
girl 1 : you're so ugly no wonder you get bullied
girl 2: Have you seen your face? Not even plastic can fix that
Used to underscore a statement or indicate that it is not open to dispute. Originated from the word "period", which people sometimessaid at the end of their sentence to make a point. It is unclear when the "t", used for extra emphasis, was added to the end of the word.
*Mom speaking to child*: Clean up your room! You have no right to disrespect me. I'm the parent, you're the child. Periodt!