Meaning of “dubious” - Learner’s Dictionary

dubious

adjective uk us /ˈdjuːbiəs/
NOT TRUE

thought not to be completely true, honest, or legal:

dubious evidence
a man with a dubious reputation
DOUBTING

not certain that something is good or true:

He's dubious about the benefits of acupuncture.
dubiously adverb

(Definition of “dubious” from the Cambridge Learner’s Dictionary © Cambridge University Press)