A model is a representation of something. It captures not all attributes of the represented thing, but rather only those seeming relevant. The model is created for a certain purpose and stakeholders.
a physical, mathematical, or otherwise logical representation of a system, entity, phenomenon, or process (DoD 1998);
a representation of one or more concepts that may be realized in the physical world (Friedenthal, Moore, and Steiner 2009);
a simplified representation of a system at some particular point in time or space intended to promote understanding of the real system (Bellinger 2004);
an abstraction of a system, aimed at understanding, communicating, explaining, or designing aspects of interest of that system (Dori 2002);
a selective representation of some system whose form and content are chosen based on a specific set of concerns; the model is related to the system by an explicit or implicit mapping (Object Management Group 2010).
