For the purposes of this article:

(1) "Abutter" shall include the owner or owners, as of the date of service of, or the date of the first publication of, a notice under the provisions of section eight of this article, of the property abutting on any street, alley, public way or easement, or sewer right-of-way or easement, upon or in which an improvement shall be made or proposed to be made under the provisions of this article;

(2) "Engineer" shall mean the municipal engineer, or, if the municipality has no regularly employed municipal engineer, any registered professional engineer, if there be any practicing in the municipality or the county, or if no such engineer be practicing in the county, any competent civil engineer;

(3) "Petitioner" shall, unless the context clearly indicates otherwise, include those abutters, whether one or more, who file the petition and bond described in section four of this article;

(4) "Improvement" shall include the grading, regrading, paving, repaving, surfacing, resurfacing, curbing, recurbing and repairing of streets, alleys, public ways or easements, or portions thereof, and the building, renewing and repairing of sidewalks, and the constructing, renewing and repairing of storm or sanitary or combined storm and sanitary sewer systems, or portions thereof, upon or in any streets, alleys, public ways or easements, or sewer rights-of-way or easements, or portions thereof, independently or in conjunction with other of such improvements, within the municipality; and

(5) "Total cost" shall include the cost and expense of surveys, engineering and attorney fees, the printing and publishing in relation thereto, and the cost and expense of all labor, work, supervision, inspection, equipment leased and materials furnished and used in completing said improvements, excepting, however, any salaries and wages paid to municipal employees that would have been paid regardless of the work on the proposed improvement.