Noun determining factor has 2 senses

• determining factor(n = noun.cognition) causal factor, determinant, determinative, determiner - a determining or causal element or factor; "education is an important determinant of one's outlook on life"
is a kind of cognitive factor
has particulars: clincher, decisive factor, influence

• determining factor(n = noun.communication) clincher, determiner - an argument that is conclusive; Array
is a kind of argument, statement