slash, scratch, scrap, toss (out), kill, black out, nix, retract, revoke, rescind, nullify, void, invalidate, undo, countermand, scuttle (a plan), overturn, negate, wipe out/clean, delete, cross out, veto, cancel (out), eliminate, reverse (a decision), abolish, contradict, override, do away with, obliterate (all traces of something)

turn over, flip, invert, obviate, revoke, welsh, welch, nullify, invalidate, annul, tip over, upset, reject, turn around, capsize, overturn, turn upside down, turn on its head, flip-flop, veto, contradict, upend (order), revolutionize, repeal, disallow, overrule, make a u-turn, reverse (position/sequence/course), switch (positions), interchange, back out of (agreement), vacate

pour, disgorge, swish, splash, trickle, purl, gush, slosh, swirl, sluice, flow, stream, spill, wash over, spume, drain, cascade, merge, wash away, wash up, babble, eddy, feed into, gurgle, ebb and flow, wick

crash, roll, envelop, tip, curl, rock, rise, spray, suck, swallow, roar, fleck, gain momentum, moisten, engulf, sink, capsize, surge, swell, roil, peak, hurtle, eddy, ebb and flow, crest, salinate, come in and go out, ripple (the sand), stipple (the surface of the water), crash against, slam (the rocks)

swing, question, adapt, fluctuate, waver, doubt, vacillate, change one's mind, revise, vary, flip-flop, shift (one's perspective), alter (one's view), adjust to (new information), modify (one's views), shilly-shally, lose one's convictions, distrust (one's perspective), warm to the idea