The definition of dubious is something that is unlikely to be true.(adjective)
An example of dubious is a claim that the world is flat.
See dubious in Webster's New World College Dictionary
Origin: L dubiosus, doubtful < dubius, doubting, uncertain < du- < or akin to duo, two + IE base *bhu-, *bheu-, to be
See dubious in American Heritage Dictionary 4
Origin: From Latin dubius; see dwo- in Indo-European roots.
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