Ethics is the philosophical study of morality. The word is commonly used interchangeably with ‘morality’ to mean the subject matter of this study; and sometimes it is used more narrowly to mean the moral principles of a particular tradition, group, or individual.
Ethics can be divided into the general study of goodness, the general study of the right action, applied ethics, metaethics, moral psychology, and the metaphysics of moral responsibility.
Deigh, J. Ethics. In R. Audi (Ed), The Cambridge Dictionary of Philosophy (1995 ed.). New York: Cambridge University Press.