happening or existing before something else or before a particular time 先前的；较早的；在前的 Although not essential, some prior knowledge of statistics is desirable. 统计学的知识虽非必要，但最好是学过一点。 This information must not be disclosed without prior written consent. 未事先征得书面许可，此消息不得泄露。 Visits are by prior arrangement. 参观需要事先安排。 Please give us prior notice if you need an evening meal. 需用晚餐者，请预先通知我们。 She will be unable to attend because of a prior engagement. 因事先有别的安排，她将不能出席。
already existing and therefore more important 优先的；占先的；较重要的 - prior to
before something 在…前面的 during the week prior to the meeting 在开会前的一周内
Word Originadjective early 18th cent.: from Latin, literally ‘former, elder’, related to prae ‘before’.