no cap
phraseInformal
A American English slang term. Browse all American slang.
What it means
No lie; I'm serious. Appended to a statement to vouch for it.
Capping, on its own, means lying: 'you're capping'.
In use
That's the best pizza in the city, no cap.
He's capping, he wasn't even there.
Where it comes from
From AAVE, where 'to cap' has meant to boast or exaggerate since at least the mid-20th century. The cap emoji did a great deal to spread the current form.