demur

compunction, doubt, misgiving, qualm, scruple

cavil, quibble

argument, conflict, debate, dispute, quarrel, squabble

censure, criticism

defiance, disobedience, rebellion

distrust, distrustfulness, dubiety, incertitude, indetermination, misdoubt, mistrust, mistrustfulness, reservation, skepticism, suspicion, uncertainty

qualmishness, unease, uneasiness

reluctance, unwillingness

cavil, quibble

challenge, dare, defy, fight

conflict, debate, dispute, hassle, quarrel, squabble, wrangle

beef, bellyache, carp, caterwaul, complain, crab, croak, fuss, gripe, grouch, grouse, growl, grumble, grump, holler, keen, moan, murmur, mutter, nag, repine, scream, squawk, squeal, wail, whimper, whine, yammer, yawp (or yaup), yowl

balk, gag, stick

censure, criticize, denounce

disobey, rebel, withstand

demonstrate