dubious

Dubious is an adjective meaning doubtful or suspicious in nature; it describes something that is unreliable, of questionable value, or morally suspect. A dubious claim raises questions about its truth; a dubious source may lack credibility.

Etymology: From Latin dubius "doubtful," via Old French dubieux, it entered English in the 16th century. Originally referring to something subject to doubt, its sense broadened to imply suspiciousness or questionable integrity.

Usage: In neutral or critical tone, dubious signals skepticism about the truth or reliability of something rather than certainty. It commonly follows about or of: "dubious about the results," "dubious of the source." It can convey moral disapproval when describing motives or actions; it is stronger than "doubtful" in implying dubiousness of integrity. Adverbs: "dubiously." Noun forms include "dubiousness" (and less commonly "dubiosity").

Examples: The document contained several dubious claims. The company's origin story is dubious. He made a dubious offer that raised concerns about its legitimacy. Her dubious smile suggested she doubted the sincerity of the invitation.

See also: credibility, reliability, suspicion, skepticism, questionable.