Definition from Nolo’s Plain-English Law Dictionary

An attempt to stop others from purchasing products from, performing services for, or otherwise doing business with a company that does business with another company that is in the midst of a labor dispute. For example, if a grocery chain's clerks are on strike, and their union discourages a delivery drivers' union from moving the products of the chain's largest food supply companies, that would be a secondary boycott. The purpose of the secondary boycott is typically to exert indirect pressure on the employer to resolve the labor dispute by causing its business connections to suffer as a result of the dispute. Secondary boycotts are illegal under the National Labor Relations Act.

Definition provided by Nolo’s Plain-English Law Dictionary.

긍까 '쟤 물건 사지도 말고 거래도 하지마'하면 primary boycott이고 거래 안했으면 하는 회사의 협력업체에다 대고 '쟤랑 놀지 마'하면 secondary boycott인가봐요. 북한이랑 거래 안 하고 있는 게 primary boycott이겠고 남한 너네 북한이랑 거래하지 마 이러는 게 secondary boycott인가 봄. 오케오케

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