defeater.

Evidence or a reason that removes or weakens the grounds for accepting a belief.

Use it for

Words that belong together

• a defeater for a belief
• an undercutting defeater

On the page

The instrument's poor calibration provided a defeater for the initial inference.

Usage notes

Primary category: analysis / argumentation / evidence. Forms: Singular defeater; plural defeaters. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings. Established modern English lexical item. No separate regional spelling or grammatical inflection entry. Writing functions: evidence, evaluation, inference. Commonness: uncommon.