What's the difference between regrade and regrede?

Regrade

Definition:

(v. i.) To retire; to go back.

Example Sentences:

(1) The subjects then used one of three treatment regimens, were retested for accumulated plaque and regraded.
(2) In Wales, the education minister, Leighton Andrews, ordered the WJEC exam board to regrade Welsh students' English papers.
(3) After 30 minutes, a second injection of placebo or naloxone was given, and the patient was regraded a third time.
(4) Challenged on whether he or anyone else should do anything to restore or change the grades achieved by pupils in England in June, Gove said: "If we were to regrade, or firstly if I were to instruct Ofqual or exam boards to regrade, I would destroy the independence of the regulator.
(5) Michael Gove has condemned the "irresponsible and mistaken" decision of the Welsh education minister, Leighton Andrews, to intervene in the disputed GCSEs grades by ordering a regrading exercise.
(6) Both the location and the dimensions of the wound as well as the breaking strength of the injured muscles remained inside such narrow limits that the trauma can be regraded as constant.
(7) Areas identified by others as area 3a should probably be regraded as parts of area 3b.
(8) The regulator insisted it would be inappropriate for either of the sets of exams to be regraded.
(9) Five minutes later, the same observer regraded the patient.
(10) The documents set out their case for a regrading of GCSE English papers taken by pupils this summer.
(11) Two thousand 300 students who took exams set by the Welsh exam board WJEC in Wales have already been regraded on the orders of the Welsh government, which regulates exams set there.
(12) There has been, as Guy Standing remarks in The Precariat , an orgy of regrading and redefining jobs as less skilled so that they qualify for lower wages; there has also been a growing confidence that employers do not need to pay higher wages in every annual wage round.
(13) The alliance is demanding Ofqual , the exam regulator in England, orders a regrade or face moves to force a judicial review in the high court.
(14) The women accepted a pay increase, still less than the men, but the regrading issue was not resolved until after another strike years later, in 1984, when they were finally classified as skilled workers.
(15) All cases were regraded according to a classification of Isaacson et al into high grade and low grade B-cell mucosa associated lymphoid tissue lymphoma.
(16) There was no difference between SLE and progressive polyarthritis as regrads the cold precipitation of rheumatoid factors.
(17) The common misconception of Norrie's disease being regraded as microphthalmia or hereditary corneal dystrophy instead of phthisis is noted.
(18) All lesions were regraded blind and twice by two pathologists.
(19) If a restructuring is essential, neither they nor I can see any reason why Marie and her colleagues shouldn’t have their jobs regraded and their pay preserved.
(20) It is being brought by an alliance of pupils, schools, councils and professional bodies, who want the students regraded after the boundary for a grade C in GCSE English was raised between January and June.