A state is the current configuration of a concrete object or abstract entity’s properties, actions, and relations.
State becomes useful because it captures an entity as it is at a given moment. A concrete object or abstract entity can have properties, actions, and relations, but its state tells us how those features are currently configured. A door may be open. A child may be sleeping. A body may be sick. An argument may be unresolved. A belief may be uncertain. A system may be stable. State helps answer the question: what condition is this entity in right now?
State applies to both concrete objects and abstract entities. A concrete object has a state in the material world. A glass can be full, cracked, or falling. A tree can be alive, diseased, or cut down. These states map to empirical ideas. An abstract entity can also have a state within a rational framework. An argument can be valid, unresolved, or contradicted. A framework can be coherent, incomplete, or revised. These states map to rational ideas.
In TST metaphysics, state sits directly on the split between reality and ideas. The split makes state especially clear. A real thing has an actual state. Our idea of that thing contains a described state. John’s actual state is different from his described state of labels such as male, hungry, or awake. The labels help. They are not John. The actual state of a thing belongs to what is real. The described state belongs to the mind. We need described states because we cannot carry full reality in our heads. We simplify. But we must remember that the model is not the thing. A state description helps us think, but reality always remains richer than the description.