Ontology Posted on 11th December 201514th June 2021 by ThePD (The Project Definition) Ontology is the philosophical study of being that studies concepts and what it means to exist (e.g., the objects). Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window) Related Posted in Science and tagged ontology, science. ThePD (The Project Definition) ThePD has been developing the Preferred Project Definitions based on the actual project execution and operation experiences and knowledge with the Project Language, and sharing with you daily basis.