ETYM Latin retrogradus, from retrogradi, retrogressus, to retrograde; retro back + gradi to step: cf. French rétrograde. Related to Grade.
1. Of amnesia; affecting time immediately preceding trauma.
2. (Astronomy) Moving from east to west on the celestial sphere; or--for planets--around the sun in a direction opposite to that of the Earth.
Moving or directed backwards; degenerating; inverse.
In music, term describing a process in which the order of notes is reversed. It is used as a basic technique in 20th-century serialism, in addition to inversion. However, it also occurs in music of the Middle Ages, as a form of musical riddle, the first known example dating from the 13th century. Haydn uses retrograde motion in the third movement of his Symphony No. 47 in G 1772, as does Beethoven in the final fugue of his piano sonata Hammerklavier 1818.
1. To go back over; SYN. rehash.
2. To move back; SYN. retreat.
3. To move backward in an orbit, of celestial bodies.
4. To move in a direction contrary to the usual one; of stars and planets.