/prɪ'veɪl; prɪ`vel/
v
1 [I] ~ (among/in sth/sb) exist or happen generally; be widespread 普遍存在; 普遍发生; 盛行; 流行
*conditions prevailing in the region 该地区的普遍状况
* The use of horses for ploughing still prevails among the poorer farmers. 用马耕作的现象在贫苦农民中仍然十分普遍.
2 [I, Ipr] ~ (against/over sb/sth) (fml 文) fight successfully (against sb/sth); defeat 战胜（某人[某事物]）; 击败
*Virtue will prevail against evil. 美德定将战胜邪恶.
* The invaders prevailed over the native population. 入侵者打败了土著居民.
3 (phr v) prevail on sb to do sth (fml 文) persuade sb to do sth 劝说某人做某事
*May I prevail on you to make a speech after dinner? 可以请你在用餐後讲几句话吗?

v [I not in progressive]formal
[Date: 1300-1400; Language: Latin;Origin: praevalere, from valere 'to be strong']
if a belief, custom, situation etc prevails, it exists among a group of people at a certain time
prevail in/among etc
　the economic conditions which prevail in England and Wales
　I admired the creativity which prevailed among the young writers.
if a person, idea, or principle prevails in a fight, argument etc, they are successful in the end
　Justice will prevail.
common sense prevails/reason prevails
(=a sensible decision is made)
　He considered lying, but then common sense prevailed.
prevail over/against
　Your inner strength will enable you to prevail over life's obstacles.
prevail on/upon [prevail on/upon sb] phr v
to persuade someone
prevail on/upon sb to do sth
　She prevailed upon her father to say nothing.