“+ adjective
Etymology: un- (I) + sparing, present participle of spare
1. : not merciful or forbearing : hard , ruthless
portrait, at once unsparing and compassionate — Coleman Rosenberger
both artists have been unsparing with their social comments — American Guide Series: Minnesota
become an unsparing critic of himself and of others — Walter Silz
2. : not frugal : liberal , profuse
worked and expected others to work with the same unsparing energy — Roger Cary
has periods of niggardliness followed by impulses of unsparing generosity