Meaning of EQUIVALENCE in English

EQUIVALENCE

noun Date: circa 1541 1. the state or property of being equivalent, the relation holding between two statements if they are either both true or both false so that to affirm one and to deny the other would result in a contradiction, a presentation of terms as equivalent, equality in metrical value of a regular foot and one in which there are substitutions

Merriam Webster. Explanatory English dictionary Merriam Webster.      Толковый словарь английского языка Мерриам-Уэбстер.