(a) "Dealer" means a person registered as a dealer under section four hundred fifteen or twenty-two hundred fifty-seven of this chapter.

(b) "Commissioner" includes the office and a branch office of the commissioner and, when authorized to receive a document or fee as agent of the commissioner, the clerk of a county.

(c) "Identifying number" means the numbers, and letters if any, on a vehicle designated by the commissioner for the purpose of identifying the vehicle.

(d) "Implement of husbandry" means a vehicle designed and adapted exclusively for agricultural, horticultural or livestock raising operations or for lifting or carrying an implement of husbandry and in either case not subject to registration if used upon the highways.

(e) "Lienholder" means a person holding a security interest in a vehicle.

(f) To "mail" means to deposit in the United States mail properly addressed and with postage prepaid.

(g) "Owner" means a person, other than a lienholder, having the property in or title to a vehicle. The term includes a person entitled to the use and possession of a vehicle subject to a security interest in another person, but excludes a lessee under a lease not intended as security.

(h) "Person" means a natural person, firm, co-partnership, association or corporation.

(i) "Pole trailer" means a vehicle without motive power designed to be drawn by another vehicle and attached to the towing vehicle by means of a reach, or pole, or by being boomed or otherwise secured to the towing vehicle, and ordinarily used for transporting long or irregularly shaped loads such as logs, poles, pipes, or structural members capable, generally, of sustaining themselves as beams between the supporting connections.

(j) "Security agreement" means a written agreement which reserves or creates a security interest.

(k) "Security interest" means an interest in a vehicle reserved or created by agreement and which secures payment or performance of an obligation. The term includes the interest of a lessor under a lease intended as security. The term also includes an interest in a vehicle pursuant to a lien arising under section two hundred eleven of the lien law and section one hundred eleven-u of the social services law. A security interest is "perfected" when it is valid against third parties generally, subject only to specific statutory exceptions.

(l) "Special mobile equipment" means a vehicle not designed for the transportation of persons or property upon a highway and only incidentally operated or moved over a highway, which if registered would be registered pursuant to schedule F of subdivision seven of section four hundred one of this chapter.

(m) "State" means a state, territory or possession of the United States, the District of Columbia, the Commonwealth of Puerto Rico, or a province of the Dominion of Canada.

(n) "Vehicle" means a vehicle as defined in section one hundred fifty-nine of this chapter except that it shall not include a device for which a registration is denied pursuant to section four hundred-a of this chapter and, except with respect to section twenty-one hundred two of this article, shall also mean a vessel as defined in section twenty-two hundred fifty of this chapter. Unless otherwise specified, "vehicle" also means a "mobile home" or a "manufactured home" as defined in section one hundred twenty-two-c of this chapter.