The verb avert means to prevent something bad from happening.
Synonyms are avoid, deter, fend off, or prevent.
The word origins from Old French (12th century) avertir meaning “turn, direct, avert, make aware”, from Vulgar Latin advertire, and Latin avertere meaning “to turn away, to drive away, shun, ward off, alienate”. It comes from ab meaning “off, away from” plus vertere meaning “to turn”. The meaning “ward off, prevent the occurrence of” is from 1610s.
He didn’t avert his gaze this time.
The bright signages can avert tragedy at night.
They tried to avert death from COVID19.