As used in this Title:
(1) "Local governmental subdivision" means a parish or municipality.
(2) "Political subdivision" means a parish, municipality, and any other unit of local government, including a school board and a special district, authorized by law to perform governmental functions.
(3) "Vacancy" occurs in an elective office when the office is or will be unoccupied for any of the following reasons:
(a) Death of the official who was elected to the office.
(b) Retirement or resignation of the official who was elected to the office.
(c) Removal from office by any means.
(d) Failure to take office for any reason or when it becomes certain that the person elected to the office will not take the office on the day when the term for which the person was elected commences.
(e) The person elected to or holding the office no longer meets the residence or domicile requirements of that office, any declaration of retention of domicile to the contrary notwithstanding.
(f) An office is created due to a reclassification of a municipality.
(g) Failure of any candidate to qualify for the election to the office or the failure of a sufficient number of candidates to qualify for the number of positions to be filled in the office.