overspend

verb

1. To spend too much money; especially, to spend more than one earns.

   “To get out of debt, first keep a budget and be careful not to overspend.”

noun

1. The amount by which someone or something is overspent.

   “Whether an underspend or overspend is significant depends upon the size of the budget. A £1,000 overspend on an £8,000 drugs budget is very significant, but a £1,000 overspend may not be significant on a £300,000 ward budget.”

   “Electrification was not included in anticipated CP6 spending, after cost uncertainties following the Great Western Main Line overspend led to cutbacks by the Department of Transport to contain costs.”