Being part of domain engineering, domain analysis enables identifying domains and capturing their ontologies in order to assist and guide system developers to design domain-specific applications. Several studies suggest using metamodeling techniques for modeling domains and their constraints. However, these techniques use different notions, and sometimes even different notations, for defining domains and their constraints and for specifying and designing the domain-specific applications. We propose an Application-based DOmain Modeling (ADOM) approach in which domains are treated as regular applications that need to be modeled before systems of those domains are specified and designed. This way, the domain models enforce static and dynamic constraints on their application models. The ADOM approach consists of three-layers and defines dependency and enforcement relations between these layers. In this paper we describe the ADOM architecture and validation rules focusing on applying them t...