Princeton's WordNet

1. foolproof, unfailing(adj)

   not liable to failure

   "a foolproof identification system"; "the unfailing sign of an amateur"; "an unfailing test"

2. unfailing(adj)

   always able to supply more

   "an unfailing source of good stories"; "a subject of unfailing interest"

3. unfailing, unflagging(adj)

   unceasing

   "unfailing loyalty"; "unfailing good spirits"; "unflagging courtesy"

Wiktionary

1. unfailing(Adjective)

   inexhaustible

2. unfailing(Adjective)

   changeless

3. unfailing(Adjective)

   infallible

Webster Dictionary

1. Unfailing(adj)

   not failing; not liable to fail; inexhaustible; certain; sure

• onophoudelikAfrikaans
• دائِم، لا يَكِلُّ، لا يَنْضَبArabic
• неизчерпаемBulgarian
• constantePortuguese (BR)
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• konstantDanish
• αμείωτος, ανεξάντλητος, συνεχήςGreek
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• lakkamatuEstonian
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