As used in this article, the following terms shall have the meanings indicated:
A person or persons who filed a claim for sewer rental rebate and was 65 years of age or over and whose spouse, if residing with the claimant, was 65 years of age or over during the calendar year in which sewer rentals were due and payable. If sewer rentals are charged to more than one individual, the number of persons to whom the sewer rental is charged shall be considered the "claimant."
All income received by the claimant during a calendar year for which the sewer rental rebate is being claimed.
All income from whatever source derived, including but not limited to salaries, wages, bonuses, commissions, income from self-employment, alimony, support money, cash, public assistance and relief; the gross amount of any pensions or annuities, including railroad retirement benefits and all benefits received under the Federal Social Security Act, except Medicare; all benefits received under state unemployment insurance laws and veterans' disability payments; all interest received from the federal or any state government or any instrumentality or political subdivision thereof; realized capital gains, rentals, workmen's compensation and the gross amount of life insurance benefits and proceeds, the gifts of cash or property in excess of $300, but shall not include surplus food or other relief in kind supplied by a governmental agency.