put a lid or cover on

he capped his pen

provide a fitting climax or conclusion to

he capped a memorable season by becoming champion of champions

place a limit or restriction on (prices, expenditure, or borrowing)

council budgets will be capped

be chosen as a member of a particular sports team, especially a national one

he was capped ten times by England

confer a university degree on

(especially in African American usage) speak in an untruthful or exaggerating way; lie or exaggerate

does she really have a tape with him or is she just capping for cash?

I feel like the people posting these ain't capping