The Only Use of

in various senses, including:

• questionable or doubtful that something should be relied upon -- as in "The argument relies on a dubious assumption."
• suspicious or doubtful that something is morally proper -- as in "The company is accused of using dubious sales practices to influence minors."
• bad or of questionable value -- as in "The state has the dubious distinction of the highest taxes."
• uncertain or doubtful -- as in "She is dubious about making the change."