Tractor
late 18th century (in the general sense ‘someone or something that pulls’): from Latin, from tract- ‘pulled’, from the verb trahere .
wiktionary
Formed from Latin tractus, perfect passive participle of trahere(“to pull”), + agent noun suffix -or.
etymonline
tractor (n.)
1856, "something that pulls," from Modern Latin tractor "that which draws," agent noun from past participle stem of Latin trahere "to pull, draw" (see tract (n.1)). Earlier used of a quack device consisting of two metal rods which were supposed to relieve rheumatism (1798, in full Perkins's metallic tractor); still the main sense in Century Dictionary (1891).
Sense of "an engine or vehicle for pulling wagons or plows" is recorded by 1896, from earlier traction engine (1859). The meaning "powerful truck for pulling a freight trailer" is first found 1926; tractor-trailer as "combined motor-truck and trailer" is from 1914.
