; (2) by inserting after paragraph (4) the following: (5) front underride guard means a device installed on or near the front of a motor vehicle that limits the distance that a vehicle struck in the rear by the vehicle with the device will slide under the front of the striking vehicle. ; (3) by inserting after paragraph (11), as redesignated, the following: (12) passenger motor vehicle has the meaning given that term in section 32101. (13) rear underride guard means a device installed on or near the rear of a motor vehicle that limits the distance that the front end of a vehicle striking the rear of the vehicle with the device will slide under the rear of the impacted vehicle. ; (4) by inserting after paragraph (14), as redesignated, the following: (15) Secretary means the Secretary of Transportation. (16) semi-trailer means a trailer, other than a pole trailer, which is designed to rest upon, or be carried by, a motor vehicle. (17) side underride guard means a device installed on or near the side of a motor vehicle that limits the distance that the front end of a vehicle striking the side of the vehicle with the device will slide under the side of the impacted vehicle. (18) single unit truck means a truck with a gross vehicle weight rating greater than 10,000 pounds (excluding any attached trailer). ; and (5) by inserting after paragraph (19), as redesignated, the following: (20) trailer means a vehicle, with or without motive power, which is designed— (A) to carry persons or property