retrograde

adjective

1. moving backward; having a backward motion or direction; retiring or retreating.
2. inverse or reversed, as order.
3. Chiefly Biology. exhibiting degeneration or deterioration.
4. Astronomy.
   1. moving in an orbit in the direction opposite to that of the earth in its revolution around the sun.
   2. appearing to move on the celestial sphere in the direction opposite to the natural order of the signs of the zodiac, or from east to west.Compare direct(def 25).
5. Music. proceeding from the last note to the first: a melody in retrograde motion.
6. Archaic. contrary; opposed.

verb (used without object), ret·ro·grad·ed, ret·ro·grad·ing.

7. to move or go backward; retire or retreat.
8. Chiefly Biology. to decline to a worse condition; degenerate.
9. Astronomy. to have a retrograde motion.

verb (used with object), ret·ro·grad·ed, ret·ro·grad·ing.

10. Archaic. to turn back.

adjective

1. moving or bending backwards
2. (esp of order) reverse or inverse
3. tending towards an earlier worse condition; declining or deteriorating
4. astronomy
   1. occurring or orbiting in a direction opposite to that of the earth’s motion around the sunCompare direct (def. 18)
   2. occurring or orbiting in a direction around a planet opposite to the planet’s rotational directionthe retrograde motion of the satellite Phoebe around Saturn
   3. appearing to move in a clockwise direction due to the rotational period exceeding the period of revolution around the sunVenus has retrograde rotation
5. biology tending to retrogress; degenerate
6. music of, concerning, or denoting a melody or part that is played backwards
7. obsolete opposed, contrary, or repugnant to

verb (intr)

8. to move in a retrograde direction; retrogress
9. US military another word for retreat (def. 1)

adj.

late 14c., originally of the apparent motions of planets, from Latin retrogradus “going back, going backward,” from retrogradi “move backward,” from retro- “backward” (see retro-) + gradi “to go, step” (see grade (n.)). General sense of “tending to revert” is recorded from 1530s.

adj.

1. Moving or tending backward.
2. Opposite to the usual order; inverted or reversed.
3. Reverting to an earlier or inferior condition.

v.

1. To move or seem to move backward; recede.
2. To decline to an inferior state; degenerate.

1. Having a rotational or orbital movement that is opposite to the movement of most bodies within a celestial system. In the solar system, retrograde bodies are those that rotate or orbit in a clockwise direction (east to west) when viewed from a vantage point above the Earth’s north pole. Venus, Uranus, and Pluto have retrograde rotational movements. No planets in the solar system have retrograde orbital movements, but four of Jupiter’s moons exhibit such movement.
2. Having a brief, regularly occurring, apparently backward movement in the sky as viewed from Earth against the background of fixed stars. Retrograde movement of the planets is caused by the differing orbital velocities of Earth and the body observed. For example, the outer planets normally appear to drift gradually eastward in the sky in relation to the fixed stars; that is, they appear night after night to fall a little farther behind the neighboring stars in their westward passage across the sky. However, at certain times a particular planet appears briefly to speed up and move westward a bit more quickly than the neighboring stars. This happens as Earth, in its faster inner orbit, overtakes and passes the planet in its slower outer orbit; the appearance of moving counter to its usual eastward drift is thus simply the result of perspective as seen from Earth. Compare prograde.