1856, "something that pulls," earlier used of a quack device consisting of two metal rods which were supposed to relieve rheumatism (1798, in full Perkins's metallic tractor
), from M.L. tractor,
from stem of L. trahere
"to pull, draw" (see tract
(1)). Sense of "an engine or vehicle for pulling wagons or plows" is first recorded 1901, from earlier traction engine
(1859). The meaning "powerful truck for pulling a freight trailer" is first found 1926; tractor-trailer
is attested from 1949.