ethics

(used with a singular or plural verb) a system of moral principles:

(used with a plural verb) the rules of conduct recognized in respect to a particular class of human actions or a particular group, culture, etc.: Christian ethics.

(used with a plural verb) moral principles, as of an individual:

(used with a singular verb) that branch of philosophy dealing with values relating to human conduct, with respect to the rightness and wrongness of certain actions and to the goodness and badness of the motives and ends of such actions. Compare axiological ethics, deontological ethics.