Definition of parallel motion in English:

parallel motion

noun

  • 1The motion of bodies which are moving in parallel directions, of one body in a direction parallel to another, or of a body which points in the same direction at every point of the motion.

  • 2A mechanical device which converts alternating rectilinear motion into circular motion, and vice versa.

  • 3Music a movement of two parts or voices in the same direction, maintaining the same interval between them.

Origin

Early 18th century; earliest use found in Ephraim Chambers (?1680–1740), encyclopaedist.