infallible
🇺🇸
/ɪnˈfæləbl/
🇬🇧
/ɪnˈfæləbl/
adjective
R
always correct; without errors
Even the most experienced teachers can't be infallible in predicting student performance.
R
always effective; never failing
His infallible sense of direction made him an excellent tour guide.
translation
always correct; without errors; always effective; never failing