determinant

definition: having the power or quality of deciding
example:
speech part: adjective
synonyms: deciding
definition: a determining or causal element or factor
example: education is an important determinant of one's outlook on life
speech part: noun
synonyms: determinative determiner determining factor causal factor
definition: a square matrix used to solve simultaneous equations
example:
speech part: noun
synonyms:
definition: the site on the surface of an antigen molecule to which an antibody attaches itself
example:
speech part: noun
synonyms: antigenic determinant

How determinant is being used?