The accuracy of an abstraction relates to the aspects that the abstraction is true to the target concept it describes. If there are contradictions between the abstraction and the reality of the target concept, then the description is not accurate. If everything from the description is true to the reality of the target concept, then the description is accurate.
Reality is based on the perception of the Entity. That means each entity determines it's own reality.
When subject entity has an abstraction about the target entity, the accuracy of the subject entity's abstraction is judged against the target entity's reality.
Relates to precision, information, scope, resolution.
Cultural Definition
The state of being accurate; freedom from mistakes, this exemption arising from carefulness; exactness; nicety; correctness "The value of testimony depends on its accuracy."
Exact conformity to truth, or to a rule or model; degree of conformity of a measure to a true or standard value.
Accuracy and Precision (Wikipedia)
accuracy of a measurement system is the degree of closeness of measurements of a quantity to that quantity's actual (true) value
Pattern Expression
Accuracy is a pattern that is applicable anywhere in Existence.