An omnibus spending bill is a type of bill in the United States that packages many of the smaller regular appropriations bills into one larger single bill that could be passed with only one vote in each house. There are twelve different regular appropriations bills that need to be passed each year to fund the federal government and avoid a government shutdown; an omnibus spending bill combines one or more of those bills into a single bill.

Every year, Congress must pass bills that appropriate money for all discretionary government spending. Generally, one bill is passed for each sub-committee of the twelve subcommittees in the U.S. House Committee on Appropriations and the matching 12 subcommittees in the United States Senate Committee on Appropriations.

Often, omnibus spending bills are criticized for being full of pork (unnecessary/wasteful spending that pleases constituents or special interest groups).[5] The bills regularly stretch to more than 1,000 pages. Nevertheless, such bills have grown more common in recent years.[1]:14

https:// en.wikipedia.org/wiki/Omnibus_spending_bill

Funds for budgets must be appropriated before they can be spent. A typical budget contains line items within groupings such as Materials and Service, Personnel, Capital Expenses, etc. The Materials and Service category can contain 100 or more individual line items. These line items when added together make the grand total for Material Services. It is common to overspend on line items as long as the total for Materials and Services isn't exceeded. If that is exceeded then you have to get a budget amendment to exceed it. Since a valid budget for the government hasn't been passed in years, I don't know what is being used - maybe the budget from 20 years ago? Who knows. But I can say that for the government to be operating without a valid budget to guide it is fiscally irresponsible and the senate and congress needs to get off their collective self-serving asses and live up to their responsibility to the people.