To prevent something from happening
prevent verb
to stop something from happening
stop verb
to prevent someone from doing something, or to prevent something from happening
avoid verb
to try to prevent something from happening
interfere with phrase
to prevent something from happening or developing in the correct way
head off phrase
to prevent something from taking place
avert verb
to prevent something bad or harmful from happening
prohibit verb
to prevent something from happening or being done
squash verb
to prevent something from happening or developing
knock something on the head phrase
to prevent something from happening
get in the way of something phrase
to prevent something from happening