The statue of his successor, Nicholas IV

(1288-1292), who was buried in the Later an, may be seen in the retro choir . C. C. Perkins , Italian Sculpture, Int., p. liv. close1.j pin is retroclusion (re-tro-klözhon), n. [L. retro , back, behind, + -clusio (n-), in comp., claudere , pp. clausus , in comp. -clusus , close: see close1.j A method of acupre ure in which the pin pa ed into the ti ue, over the artery, then, turning in a semicircle, is brought out behind the artery, the point of the pin coming out near its entrance. retrocollic (re-tro-kol'ik), a. [L. retro , back, behind, + collum , neck: see collar .] Pertaining to the back of the neck.- Retrocollic spasm, spasm of the muscles on the back of the neck, tonic or clonic. [ retrocopulant (rē-trō-kop'ū-lant), a . tro , back, behind, + copulan (t-)s, ppr. of copu lare , copulate: see copulate .] Copulating backward or from behind. retro copulate (re-tro-kop'ū-lāt), v . i . [ tro , back, behind, + copulatus , pp. of copulare , copulate: see copulate .] To copulate from behind or aversely and without ascension, as va retrogradation (retro or rē"trō-grā-dā'shon), [ retrogradation , F. rétrog rad at i on = Pr.retro grad a cio = Sp. retro grad a cion = Pg. re trogradação = It. retro grad azione , retro gradatio ( n- ), a going back, retro grad are , pp. retro grad at us, a later form of L. retro grad i , go backward: see retrograde .] 1. The act of retrograding or moving backward; specifically, in astron ., the act of moving from east to west relatively to the fixed stars, or contrary to the order of the signs and the usual direction of planetary motion: applied to the apparent motion of the planets. Also retrogre ion . Planets have their stations and retrogradations , as well as their direct motion. Cudworth , Sermons, p. 58. ( Latham .) 2. The act of going backward or losing ground; hence, a decline in strength or excellence; de terioration. retrograde (retro or retro-grad), v . [ retro grader , recoil, F. rétrograder = Pr. Sp. Pg. retrogradar = It. retro grad are , retro grad are , later form of L. retro grad i , go backward, retro , backward, + grad i , go: see gradel .] I. in trans . 1. To go backward; move backward. IMG:content-2132.png:[blocks in formation] retrograde grade or retrogre ive; develop a le from a more complex organization; degenerate. Of all existing species of animals, if we include parasites, the greater number have retrograded from a which their remote ancestors had once advanced. H. Spencer , Prin. of Sociol., § 50.