reliability

UK: /rɪˌlaɪəˈbɪlɪti/ US: /rɪˌlaɪəˈbɪlɪti/

WordReference Random House Learner's Dictionary of American English © 2026

re•li•a•ble /rɪˈlaɪəbəl/   adj. 

1. capable of being relied on; always or often dependable in character, judgment, performance, or result:
   a reliable source of information.

re•li•a•bil•i•ty /rɪˌlaɪəˈbɪlɪti/  n. [uncountable]
re•li•a•bly, adv. 

WordReference Random House Unabridged Dictionary of American English © 2026

re•li•a•ble  (ri lī′ə bəl), adj. 

1. that may be relied on;
   dependable in achievement, accuracy, honesty, etc.:
   reliable information.

• rely + -able 1560–70

re•li′a•bil′i•ty, re•li′a•ble•ness, n. 
re•li′a•bly, adv. 
Synonyms

trusty, authentic, consistent. Reliable, infallible, trustworthy apply to persons, objects, ideas, or information that can be depended upon with confident certainty. Reliable suggests consistent dependability of judgment, character, performance, or result:
a reliable formula, judge, car, meteorologist.
Infallible suggests the complete absence of error, breakdown, or poor performance:
an infallible test, system, marksman.
Trustworthy emphasizes the steady and honest dependability which encourages one's confidence, belief, or trust:
trustworthy and accurate reports.

Antonyms

undependable, questionable, deceitful.