Something's plausibility is how likely it is to be true. You might, for example, question the plausibility of your brother's story about seeing a UFO land in the back yard.

The noun plausibility means "likelihood" or "believability." You're most likely to come across the word in a negative or questioning context, as when someone doubts the plausibility of an action movie's plot or questions the plausibility of a debater's claims and arguments. If you aren't sure you believe something, you'll question its plausibility. The Latin root is plausibilis, "deserving applause or acceptable."

Definitions of plausibility
  1. noun
    apparent validity
    synonyms: plausibleness
    see moresee less
    implausibility, implausibleness
    the quality of provoking disbelief
    reasonableness, tenability, tenableness
    the quality of being plausible or acceptable to a reasonable person
    type of:
    believability, credibility, credibleness
    the quality of being believable or trustworthy
Word Family

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