Simple Definition of infallible

from our Learner's Dictionary

infallible

adjective

1
: not capable of being wrong or making mistakes : not fallible
I never claimed to be infallible.
an infallible memory
2
: certain to work properly or succeed
There is no infallible remedy to these problems.

Cite this Entry

“Infallible.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/infallible. Accessed 21 Jun. 2026.

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