tie-in
/ˈtaɪɪn/noun
1- a connection or association关联; 关系：
there's a tie-in to another case I'm working on.
这和我正在处理的另一个案件有关联。
1.1
- a book, film, or other product produced to take advantage of a related work in another medium（与另一媒体的作品）相互关联的书（或电影等）。
1.2
- as modifier chiefly N. Amer. denoting sales made conditional on the purchase of an additional item or items from the same supplier〈主北美〉搭卖; 搭配销售的商品。