Lewis & Short

dē-rŏgo, āvi, ātum, 1, v. a., jurid. t. t., to repeal a part of a law, to restrict or modify it.

  1. I. Prop.: huic legi nec obrogari fas est, neque derogari ex hac aliquid licet, neque tota abrogari potest, Cic. Rep. 3, 22; cf.: de lege aliquid derogare aut legem abrogare, id. Inv. 2, 45, 134; id. Cornel. I. Frag. 11: derogatur legi, cum pars detrahitur, Dig. 16, 102.
  2. II. Transf., beyond the legal sphere, to take away, detract from, to diminish, to remove, withdraw.
          1. (α) With de: de magnificentia aut de honestate quiddam, Cic. Inv. 2, 58, 175; cf. id. ib. 2, 17, 53: de testium fide, id. Caecin. 1 fin.
          2. (β) With ex: si quid ex hac ipsa (aequitate) accusator derogat, Cic. Inv. 2, 46, 136.
          3. (γ) With dat. (so most freq.): non mihi tantum derogo, tametsi nihil arrogo, ut, etc., Cic. Rosc. Amm. 32: fidem alicui, id. Fl. 4, 9; id. Div. 2, 71, 146; Luc. 9, 351; Cels. praef.; Lact. Epit. 50, 2; cf. the foll. no. B.; and simply, fidem, Cic. Quint. 23, 75: gratiam nomini, Plin. 7, 28, 29, §104: nihil universorum juri, Tac. A. 13, 27 et saep.
    1. B. With abstract subjects: quorum virtuti, generi, rebus gestis, fidem et auctoritatem in testimonio cupiditatis suspicio derogavit, Cic. Font. 7; Quint. 9, 3, 102: ubi certam derogat vetustas fidem, Liv. 7, 6, 6.
    2. C. To disparage, dishonor: et derogastis adversum me verba vostra (i. e. me verbis), Vulg. Ezech. 35, 13.