differentia

Animal” names the general class, and “reasoning” is the differentia which separates “man” from other “animals.

The differentia should include all the members that the term denotes, and it should exclude all that it does not denote.

Find the genus and differentia in the definition of “a good book of the hour.”

Wilhelmi de Northfeilde expositio super librum de differentia spiritus et anim.

But the most obvious differentia of Whiggism was a dislike to the ecclesiastical spirit.