adj. pitiless, unpitying, cruel, unsympathetic, merciless, unmerciful, harsh, fierce, remorseless, uncompassionate, vicious, savage, ferocious, hard-hearted, callous, unfeeling, tough, severe, heartless, inhuman, brutal, brutish, unrelenting, relentless, Chiefly US and Canadian mean The jail houses some of the country's most ruthless criminals In all of history there was no more ruthless a tyrant. sabotage n. 1 destruction, damage, wrecking, impairment Enemy infiltrators were responsible for the sabotage of our radar 2 subversion, treachery, treason When the radar was found damaged, sabotage was suspected
v. 3 undermine, subvert, disrupt, spoil, ruin, cripple; damage, incapacitate, disable, destroy, wreck, Colloq Brit throw a spanner in(to) the works, US throw a monkey wrench into the machinery, Slang Brit queer (someone's pitch) Only someone who had something to lose would have sabotaged our plan for reorganization The engine had been sabotaged by pouring sand into the fuel tank.