Having to pay an amount of money for something, especially if unexpected or having to pay more than one thinks is a fairprice.
"I brought the whole family to the game, which cost a fortune. To make things worse, once I got there had to shell out to buy hotdogs, icecream, sodas, and baseball hats!"
adjective - relating to consuming excessive amounts of room service, shelling out is essentially the equivalent of crabbing or lobstering in the context of a chinese buffet. shelling out is particularly embarrassing if exectued at the hotel poolside
"shall i call room service again or are you about to shell out?"
The set of delaying tactics, mystified looking around moves and "where the hell's my wallet" self-frisking someone makes when they want you to pickup the check.
He's in a startup now and won't pay for anything, all he'll do is pull a Shell-out Falter on you.