Simple Definition of infallible
: not capable of being wrong or making mistakes : not fallible
: certain to work properly or succeed
Full Definition of infallible
Examples of infallible
I never claimed to be infallible.
There is no infallible remedy to these problems.
Origin of infallible
Middle English, from Medieval Latin infallibilis, from Latin in- + Late Latin fallibilis fallible
First Known Use: 15th century
INFALLIBLE Defined for Kids
Seen and Heard
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