Disadvantageous \Dis*ad`van*ta"geous\, a. [Cf. F. d['e]savantageux.] Attended with disadvantage; unfavorable to success or prosperity; inconvenient; prejudicial; -- opposed to {advantageous}; as, the situation of an army is disadvantageous for attack or defense. [1913 Webster] Even in the disadvantageous position in which he had been placed, he gave clear indications of future excellence. --Prescott. -- {Dis*ad`van*ta"geous*ly}, adv. -- {Dis*ad`van*ta"geous*ness}, n. [1913 Webster]