What is the definition of symmetric in the Properties of congruence?

When in a triangle, for angle A, B, C; As the symmetric property of congruence , when ∠A ≌ ∠B then ∠B ≌ ∠A and when ∠A ≌ ∠C then ∠C ≌ ∠A and when ∠C ≌ ∠B then ∠B ≌ ∠C

This is the definition of symmetric property of congruence.