prevent from doing something or being in a certain state; "We must prevent the cancer from spreading"; "His snoring kept me from falling asleep"; "Keep the child from eating the marbles"
To prevent someone from doing something means to make it impossible for them to do it. He said this would prevent companies from creating new jobs The police have been trying to prevent them carrying weapons. to stop something from happening, or stop someone from doing something (past participle of praevenire )
keep from happening or arising; have the effect of preventing; "My sense of tact forbids an honest answer"
To prevent something means to ensure that it does not happen. These methods prevent pregnancy Further treatment will prevent cancer from developing We recognized the possibility and took steps to prevent it happening. + prevention pre·ven·tion the prevention of heart disease. crime prevention
keep from happening or arising; have the effect of preventing; "My sense of tact forbids an honest answer