[1] : The Collaborative International Dictionary of English v.0.48

unsparing \unspar"ing\, a. pref. un- not + sparing, p. pr. of
   spare.
   1913 webster
   1. not sparing; not parsimonious; liberal; profuse. --burke.
      1913 webster

   2. not merciful or forgiving. r. --milton.
      1913 webster -- unspar"ingly, adv. --
      unspar"ingness, n.
      1913 webster
see also:
unspar"ingly unspar"ingness 

[2] : WordNet (r) 2.0

unsparing
     adj 1: very generous; "distributed gifts with a lavish hand"; "the
            critics were lavish in their praise"; "a munificent
            gift"; "his father gave him a half-dollar and his
            mother a quarter and he thought them munificent";
            "prodigal praise"; "unsparing generosity"; "his
            unstinted devotion"; "called for unstinting aid to
            britain" syn: lavish, munificent, overgenerous,
             prodigal, too-generous, unstinted, unstinting
     2: not forbearing; ruthless; "an unsparing critic"
see also:
lavish munificent overgenerous prodigal too-generous unstinted 
unstinting 

[3] : Moby Thesaurus II by Grady Ward, 1.0

71 moby thesaurus words for "unsparing":
   spartan, spartanic, ardent, assiduous, astringent, austere,
   authoritarian, bighearted, bounteous, bountiful, demanding,
   diligent, dour, energetic, exacting, exigent, fervent, free,
   freehanded, freehearted, generous, giving, gracious, greathearted,
   grim, handsome, hard, hardworking, harsh, hospitable, inclement,
   indefatigable, industrious, laborious, large, largehearted, lavish,
   liberal, magnanimous, meticulous, munificent, never idle, open,
   openhanded, openhearted, princely, profuse, relentless, rough,
   rugged, sedulous, severe, sleepless, stern, stintless, strenuous,
   strict, stringent, tireless, tough, unflagging, ungentle,
   ungrudging, unremitting, unselfish, unsleeping, unstinted,
   unstinting, unwearied, vehement, zealous

Unsparing >> U Words
Unsparing, definition of term: Unsparing
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