here's the IRS definition from the 1040 instructions
Gross income means all income you received in the form of money, goods, property, and services that isn't exempt from tax, including any income from sources outside the United States or from the sale of your main home (even if you can exclude part or all of it). it does not include the money you spend on her/them.
for a better idea of various categories look at a 1040 page 1 lines 1 through 7 and schedule 1 lines 1 through 8. As you can see there are many possibilities but your statement about her would seem to eliminate most of them.
workers compensation paid to survivors is exempt from taxation under IRC 104(a) so would not be included in gross income
