binder
n. countable B2 Upper Intermediate US //ˈbaɪndɝ// UK //bˈaɪndɐ// binder
n. a person or thing that holds other people or things together. You use it for a book folder, a glue, or a leader who keeps a group united.
n. an agent or substance that binds, holds together, or unites separate elements. In computing, it refers to a program that links compiled code; in law, a document that secures an obligation.
She put her notes in a plastic binder.
The project manager acted as a binder, keeping the design and engineering teams aligned on the deadline.
The legal binder secured the transaction terms, ensuring that both parties remained committed to the sale until the final closing date.
From Middle English byndere; equivalent to bind + -er.