preventive

US /prɪˈven.t̬ɪv/
UK /prɪˈven.t̬ɪv/
1.

予防

designed to keep something undesirable such as illness, harm, or accidents from occurring.

:
preventive medicine
1.

予防

a medicine or other treatment designed to stop disease or ill health from occurring.

:
quinine was used as a malaria preventive