third-row seat
Refers specifically to the rearmost seating row in a multi-row vehicle such as a minivan or SUV. Wasei-eigo; not used in English.
wasei-eigo (Japanese-coined English), from third seat
This minivan has a spacious and comfortable third-row seat.
If you fold down the third-row seat, the cargo space becomes much larger.
Variant with a middle dot, sometimes used in catalogs or specifications.
Wasei-eigo from English 'third' and 'seat'. It is wasei.