«الإجماع في اللغة: الاتفاق»
In language, ijma‘ means agreement.
Agreement means that people share the same position on a matter rather than disagreeing about it. This is the broad linguistic sense; a group agreeing on a practical plan illustrates mere agreement.
Technical ijma‘, however, is not just any group decision. Juristic qualification, belonging to the relevant community, a shared period, and the matter under consideration make the technical meaning narrower. We therefore need the book’s legal definition.