Wiktionary
unplausible
a. (alternative form of implausible English)
Usage examples of "unplausible".
His senses had not been assailed by any noisome effluvia This was no unplausible ground for imagining that this death had some other cause than the yellow fever.
He must have had some reasons, and perhaps not unplausible ones, for this affirmation, of which all his hearers, as they had the accounts lying before them, were at that time competent judges.
And this pity finds expression in wistful sympathy when we think of the quixotic strain in this wrestling with an overwhelming foe, when we see the childlike faith with which the people have grasped at every unplausible hope of rescue from its anguish of death and still grasps at it, as a drowning man grasps at a wisp of straw.