The act or process of disproving; an instance of showing something to be false.
From disprove + -al (noun suffix). This creates a noun meaning the action of disproving, though it's quite rare compared to 'disproof.'
While we have both 'disproof' and 'disproval' meaning essentially the same thing, disproof won out in modern English—it's a reminder that even in English, one synonym often dominates.
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