humanus

Humanus, humana, humanum is first and second declension, from homo, and both are ultimately from humus, "earth": a human being is the creature made of soil, which is the same joke the Hebrew of Genesis makes with adam and adamah.

Two senses run in parallel. The plain one is "belonging to people", as in res humanae, human affairs, usually set against res divinae. The loaded one is "civilised, cultivated, kindly", and that is the sense behind humanitas, which for Cicero means education and decency together, and behind the humanities as a name for a syllabus. Terence's "homo sum, humani nihil a me alienum puto" uses the neuter as a noun: nothing human is foreign to me.