Currently Not Collectible
Currently Not Collectible is the term the IRS uses when your current financial situation does not afford you to pay the IRS after you have paid your living expenses each month.
The IRS wants food on your table, a roof over your head and clothes on your back first. After that, if you do not have money left over each month, they will agree to put all collection activity on hold until your situation improves.
This is a temporary solution that, when combined with other solutions, can help get you back on your feet, financially.