1560s, "lower in position, rank, or dignity, impair morally," from de- "down" + base (adj.) "low," on analogy of abase (or, alternatively, from obsolete verb base "to abuse"). From 1590s as "lower in quality or value" (of currency, etc.), "degrade, adulterate." Related: Debased; debasing; debasement.

"weaken, impair the strength of, enfeeble, make inactive or languid," 1530s, from Latin debilitatus, past participle of debilitare "to weaken," from debilis "weak, helpless," from de "from, away" (see de-) + -bilis "strength," from PIE root *bel- "strong" (see Bolshevik). Related: Debilitated; debilitating.

"deterioration, a becoming worse," 1650s, noun of action from pejorate (1640s), from Late Latin peiorare "make worse," from Latin peior "worse," perhaps originally "stumbling," from PIE *ped-yos-, suffixed (comparative) form of *ped- "to walk, stumble, impair," from root *ped- "foot." Meaning "a lowering or deterioration of the sense of a word" is by 1889.

late 14c., "mar the external figure of, impair the beauty, symmetry, or excellence of," also "transform the appearance of, disguise," from Old French desfigurer "disfigure, alter, disguise, destroy," from Medieval Latin diffigurare, from assimilated form of Latin dis- (see dis-) + figurare "to form, shape," from figura "a shape, form, figure" (from PIE root *dheigh- "to form, build"). Related: Disfigured; disfiguring; disfiguration.

"depreciative, disparaging, giving a low or bad sense to," 1888, from French péjoratif, from Late Latin peiorat-, past-participle stem of peiorare "make worse," from Latin peior "worse," perhaps originally "stumbling," from PIE *ped-yos-, suffixed (comparative) form of *ped- "to walk, stumble, impair," from root *ped- "foot." As a noun, "a word that depreciates the sense," from 1882. English had a verb pejorate "to worsen" from 1640s.