The term GIVE A BAD REVIEW TO can be summarized by two words: PAN and SLAM. PAN is a verb meaning to criticize harshly, while SLAM is a verb meaning to criticize severely. Both words are used to describe the act of giving a bad review to someone or something. This could be a review of a product, service, or performance. In either case, the reviewer is expressing their dissatisfaction with the subject of the review.