undependable, unreliable(adj)

liable to be erroneous or misleading

"an undependable generalization"

unreliable, undependable(adj)

not worthy of reliance or trust

"in the early 1950s computers were large and expensive and unreliable"; "an undependable assistant"

treacherous, unreliable(adj)

dangerously unstable and unpredictable

"treacherous winding roads"; "an unreliable trestle"

unreliable(adj)

lacking a sense of responsibility

unreliable(adjective)ˌʌnrɪlˈaɪəbəl

not able to be believed or trusted

so unreliable that you can never expect him to be here on time; unreliable evidence

unreliable(Adjective)

Not reliable.

Unreliable(adj)

not reliable; untrustworthy. See Reliable