Rototiller (n.)

1873, an irregular shortening of rotator, originally in mathematics. Mechanical sense of "rotating part of a motor" is attested by 1903; specifically of helicopters from 1930.

mid-14c., "stock of a crossbow," from Old French telier "stock of a crossbow" (c. 1200), originally "weaver's beam," from Medieval Latin telarium, from Latin tela "web; loom," from PIE *teks-la-, from root *teks- "to weave," also "to fabricate." Meaning "bar to turn the rudder of a boat" first recorded 1620s.