Meaning of EXPONENT in English

noun one who, or that which, stands as an index or representative; as, the leader of a party is the exponent of its principles.

2. exponent ·noun a number, letter, or any quantity written on the right hand of and above another quantity, and denoting how many times the latter is repeated as a factor to produce the power indicated.

Webster English vocab.      Английский словарь Webster.