When saying how much I have to spend, I only say the number. If I have to refer to it in some way (i.e. choice for Minion or Pawn) then I use money and coins interchangeably.
Piledrive = to buy many cards from a pile quickly.
Sneak ending = to end the game in a 3-pile when the opponent didn't seem to see it coming.
(Small off-topic point: It is just, so incredibly important to watch for 3 piles. The ability to manipulate when the game is going to end is so useful, that I think it's the most important thing you can learn to get better at Dominion. If you know how to end or prolong a game, you know how to end with an advantage or prolong a game for a comeback.)
Steal the win = to end the game quickly in a win, where if the game had gone on for more turns I would have almost certainly lost. Usually happens from 3-piles.