undependable

Definitions of undependable

1. adjective

   not worthy of reliance or trust
   “an undependable assistant”

   synonyms: unreliable

   erratic, temperamental, wayward

   likely to perform unpredictably

   uncertain

   not consistent or dependable

   unsound

   of e.g. advice

   untrustworthy, untrusty

   not worthy of trust or belief

   antonyms:

   dependable

   worthy of reliance or trust

   certain, sure

   reliable in operation or effect

   tested, time-tested, tried, tried and true

   tested and proved to be reliable

   undeviating

   used of values and principles; not subject to change; steady

   trustworthy, trusty

   worthy of trust or belief
2. adjective

   liable to be erroneous or misleading
   “an undependable generalization”

   synonyms: unreliable

   fallible

   likely to fail or make errors