PRECEDENT

[noun] [C] - an action, situation or decision which has already happened and which can be used as a reason why a similar action or decision should be performed or takenThere are several precedents for promoting people who do not have formal qualifications.Sadly there are precedents of (= previous examples of) accidents happening at railway crossings.Some politicians fear that agreeing to the concession would set a dangerous precedent, since it might allow a whole range of changes to be introduced.Precedent is also the way that something has been done in the past which therefore shows that it is the correct way.Would it be breaking with precedent for the bride to make a speech?