Negative keywords are a priority to developing effective AdWord campaigns.For example, when you add "free" as a negative keyword to your campaign or ad group, you tell AdWords not to show your ad for any search containing the term "free." On the Display Network, your ad is less likely to appear on a site when yournegative keywords match the site's content.
AdWords: Negative KeywordsThursday, October 20, 2016
A type of keyword that prevents your ad from being triggered by a certain word or phrase. It tells Google not to show your ad to anyone who is searching for that phrase.