ˈtie-up [tie-uptie-ups] BrE NAmE noun 1.~ (with sb/sth) (BrE)an agreement between two companies to join together •They're negotiating a tie-up with Ford. 2.~ (between A and B) (BrE)a connection between two or more things •a tie-up between politics and economics 3. (especially NAmE)a situation in which sth stops working or moving forward •a traffic tie-up