determinant

nouns

a determining or causal element or factor
"education is an important determinant of one's outlook on life"
is derived from
the site on the surface of an antigen molecule to which an antibody attaches itself
a square matrix used to solve simultaneous equations
is a type of (narrower)
a matrix with the same number of rows and columns

adjectives

having the power or quality of deciding
"the crucial experiment"; "cast the deciding vote"; "the determinative (or determinant) battle"
is derived from
is derived from