1. (

• undependable ,
• unreliable

) liable to be erroneous or misleading; "an undependable generalization" ;

2. (

• unreliable ,
• undependable

) not worthy of reliance or trust; "in the early 1950s computers were large and expensive and unreliable"; "an undependable assistant" ;

3. (

• treacherous ,
• unreliable

) dangerously unstable and unpredictable; "treacherous winding roads"; "an unreliable trestle" ;

4. (

• unreliable

) lacking a sense of responsibility ;