v. 25B6; verb
a low turnout invalidated the ballot : RENDER INVALID, void, nullify, annul, negate, cancel, overturn, overrule.
this case invalidates the general argument : DISPROVE, refute, explode, contradict, rebut, negate, belie, discredit, debunk; weaken, undermine, compromise; informal shoot full of holes; formal confute.