1 a : a series of usually metal links or rings that are connected to each other in a line and used for supporting heavy things, for holding things together, for decoration, etc. [count] ▪ The neighbor's dog is kept on a chain. [=is connected to a chain that keeps it from getting away] ▪ She wore a beautiful gold chain [=necklace] around her neck. ▪ the ship's anchor chain ▪ a bicycle chain [noncount] ▪ We'll need 25 feet of chain for the pulley. —see picture and at bicycle; see also choke chain, key chain b [count] : a chain that is attached to the arms or legs of a prisoner —usually plural ▪ The prisoners were kept in chains while being transferred to the new jail. —often used figuratively ▪ The contract would keep the employees in chains, unable to leave the company for at least five years. —see also ball and chain
2 [count] : a series or group of things or people that are connected to each other in some way ▪ a chain of islands ▪ The world's longest mountain chain [=group of mountains that form a long line] is the Andes. ▪ The new book chronicles the chain of events leading up to the crime. ▪ Protesters formed a human chain [=they stood next to each other with their arms linked] around the ancient tree to prevent it from being cut down. —see also daisy chain, food chain
3 [count] : a group of businesses (such as stores, restaurants, or hotels) that have the same name and basic appearance and sell the same products or services ▪ They own a chain of organic grocery stores. ▪ fast-food/clothing chains ; also : the company that owns such a group of businesses ▪ The hotel chain recently opened a new hotel in Hong Kong. —see also chain store
4 [count] Brit : a number of people who each want to buy a house but must first sell their current house before moving to the next one —usually singular ▪ Both houses are currently vacant so there is no chain to worry about.