Antonyms of adj reliable

3 senses of reliable

Sense 1
reliable (vs. unreliable), dependable (vs. undependable) -- (worthy of reliance or trust; "a reliable source of information"; "a dependable worker")

unreliable (vs. reliable), undependable (vs. dependable) -- (not worthy of reliance or trust; "in the early 1950s computers were large and expensive and unreliable"; "an undependable assistant")
        => erratic, temperamental -- (likely to perform unpredictably; "erratic winds are the bane of a sailor"; "a temperamental motor; sometimes it would start and sometimes it wouldn't"; "that beautiful but temperamental instrument the flute"- Osbert Lancaster)
        => uncertain -- (not consistent or dependable; "an uncertain recollection of events"; "a gun with a rather uncertain trigger")
        => unsound -- (of e.g. advice)

Sense 2
dependable, honest, reliable, true (predicate) -- (worthy of being depended on; "a dependable worker"; "an honest working stiff"; "a reliable sourcSFLe of information"; "he was true to his word"; "I would be true for there are those who trust me")

INDIRECT (VIA trustworthy) -> untrustworthy, untrusty -- (not worthy of trust or belief; "an untrustworthy person")

Sense 3
authentic, reliable -- (conforming to fact and therefore worthy of belief; "an authentic account by an eyewitness"; "reliable information")

INDIRECT (VIA trustworthy) -> untrustworthy, untrusty -- (not worthy of trust or belief; "an untrustworthy person")

Similarity of adj reliable

3 senses of reliable

Sense 1
reliable (vs. unreliable), dependable (vs. undependable) -- (worthy of reliance or trust; "a reliable source of information"; "a dependable worker")
       => certain, sure -- (reliable in operation or effect; "a quick and certain remedy"; "a sure way to distinguish the two"; "wood dust is a sure sign of termites")
       => tested, time-tested, tried, tried and true -- (tested and proved to be reliable)
       => undeviating -- (used of values and principles; not subject to change; steady; "undeviating loyalty")
          Also See-> trustworthy#1, trusty#1

Sense 2
dependable, honest, reliable, true (predicate) -- (worthy of being depended on; "a dependable worker"; "an honest working stiff"; "a reliable sourcSFLe of information"; "he was true to his word"; "I would be true for there are those who trust me")
       => trustworthy (vs. untrustworthy), trusty -- (worthy of trust or belief; "a trustworthy report"; "an experienced and trustworthy traveling companion")

Sense 3
authentic, reliable -- (conforming to fact and therefore worthy of belief; "an authentic account by an eyewitness"; "reliable information")
       => trustworthy (vs. untrustworthy), trusty -- (worthy of trust or belief; "a trustworthy report"; "an experienced and trustworthy traveling companion")