Contemporary linguistic research, led by computational linguistics, has witnessed the emergence of terms that have contributed to the cross-fertilization of sciences, among which is the concept of ontology. This concept originated in a philosophical language environment. It returned, via the bridge of computational linguistics, to secure a central position in the field of semantics, through computational editors like Protégé Editor. This paper aims to establish the concept of ontology in the field of computational linguistics to emphasize its importance in semantics and clarify the differences in the meaning of “ontology” in computer science compared to its understanding in philosophical contexts. We presented this paper in three main sections: The first section discusses the concept of ontology in the field of philosophy, addressing metaphysical ontological excavations and ontology in modern philosophy. The second section examines the meaning of ontology in computational linguistics, discussing the importation of the concept into computational linguistics. The third section compares the meaning of ontology between philosophy and computer science, analyzing the structure of ontology between these fields through the Protégé editor, along with a deep comparison of its semantics. We concluded that ontology is a concept that has been imported from philosophy to computational linguistics, demonstrating the cross-fertilization of sciences and the migration of terms. The primary initial use of “ontology” is in the field of philosophy as a conceptual understanding of existence and non-existence, which implies that it contains a universal concept with its own specific terms and philosophical mechanisms. However, in the domain of computational linguistics, it represents an official and shared conception of the concept in a semantic field, aiming to facilitate both human and automated processing of language in the semantic web environment.