/ ˈplɔːzəbl; NAmE / adjective
1.
( of an excuse or explanation ) reasonable and likely to be true :
Her story sounded perfectly plausible.
The only plausible explanation is that he forgot.
OPP implausible
2.
( disapproving ) ( of a person ) good at sounding honest and sincere, especially when trying to trick people :
She was a plausible liar.
► plausi·bil·ity / ˌplɔːzəˈbɪləti; NAmE / noun [ U ]
► plaus·ibly / -əbli; NAmE / adverb :
He argued very plausibly that the claims were true.
••
WORD ORIGIN
mid 16th cent. (also in the sense deserving applause or approval ): from Latin plausibilis , from plaus- applauded, from the verb plaudere .