precaution
/prɪˈkɔːʃən/noun
1- a measure taken in advance to prevent something dangerous, unpleasant, or inconvenient from happening预防, 防备; 警惕：
he had taken the precaution of seeking legal advice.
他已经做好了寻求法律援助的准备。
1.1
precautions
informal used euphemistically to refer to contraception〈非正式, 婉〉避孕：we never took precautions.
我们从不采取任何避孕措施。
派生词
precautionary
adjective词源
late 16th cent. （in the sense 'prudent foresight'）： from French précaution, from late Latin praecautio（n-）, from Latin praecavere, from prae 'before'+cavere 'take heed， beware of'.