(1) For purposes of sections 16-617 to 16-650:
(a) Lot means a lot as described and designated upon the record plat of any city of the first class, or within a county industrial area as defined in section 13-1111 contiguous to such city. If there is no recorded plat of any such city or county industrial area, lot means a lot as described and designated upon any generally recognized map of any such city or county industrial area; and
(b) Land means any subdivided or unplatted real estate in such city or county industrial area.
(2) If the lots and real estate abutting upon that part of the street ordered improved, as shown upon any recorded plat or map, are not of uniform depth, or, if for any reason, it shall appear just and proper to the mayor and city council, they are authorized and empowered to determine and establish the depth to which such real estate shall be charged and assessed with the costs of the improvements, which shall be determined and established according to the benefits accruing to the property by reason of such improvements. Real estate may be so charged and assessed to a greater depth than lots as shown on any such plat or map.