More generally, any result of mental activity; a thought, a notion; a way of thinking.
An abstract archetype of a given thing, compared to which real-life examples are seen as imperfect approximations; pure essence, as opposed to actual examples.
A conception in the mind of something to be done; a plan for doing something, an intention.
A purposeful aim or goal; intent
A musical theme or melodic subject.
An image of an object that is formed in the mind or recalled by the memory.
A vague or fanciful notion; a feeling or hunch; an impression.
The theory of a particular philosopher or school of thought concerning the fundamental types of entity in the universe.
A logical system involving theory of classes, developed by Stanislaw Lesniewski (1886-1939).
A structure of concepts or entities within a domain, organized by relationships; a system model.
The branch of metaphysics that addresses the nature or essential characteristics of being and of things that exist; the study of being qua being.
In a subject view, or a world view, the set of conceptual or material things or classes of things that are recognised as existing, or are assumed to exist in context, and their interrelations; in a body of theory, the ontology comprises the domain of discourse, the things that are defined as existing, together with whatever emerges from their mutual implications.