A large indeterminate quantity of.
Synonymous with :
(truck/shed/shit/shelf)loads of, heaps of, masses of, piles of, mountains of, stacks of, oodles of, etc
Also see: wads of (cash), stashes of(money), barrels of (laughter/fun), bags of (fun/ money/ confidence).
"I can't come out tonight; I've got tons of work to do".
"There are tons of fun activities to do in Paris".
"Not only is she intelligent; she's got tons of confidence too".