Before revision: Decision points or independent variables with two states have a binary root that is referred to as a wiktionary:dichotomy|dichotomous key whereas, the term polychotomous key refers to roots which are greater than one or unitary and usually greater than two or binary.
After revision: Decision points or independent variables with two states have a binary root that is referred to as a dichotomous key whereas, the term polychotomous key refers to roots which are greater than one or unitary and usually greater than two or binary.