Note: This glossary is far from exhaustive, but it does serve as a decent primer for some of the most common terms one will encounter. As always, in-depth explorations of the literature are the best way to learn technical terms.
Cultural Relativism. The view that the truth of moral statements are relative to cultures, or societies. Sometimes called moral isolationism, this view holds that cultures are isolated enough entities such that morality can be relative to them.
Ethical Nonnaturalism. The view that ethical properties are not reducible to scientific, natural properties.
Moral Realism. The view that moral judgments are meant to describe the way things really are, and further that some of these judgments are true. The truth of these judgments are seen to be above the purview of any human; the standard for judging moral truths is not grounded in consent. This standard can be God, or whatever else, but what matters is that it is not a human construct.
Moral Antirealism. The view that moral judgments do not describe the fundamental reality outside of our heads, but rather derive their truth value from consent and human agency. The universe does not take sides in our moral disputes, or so the antirealist believes.
Normativity. Normativity concerns itself with the way things should be. Normative statements thus tell us how we ought to live our lives, and are in contrast with descriptive statements, which merely describe the way things are. Normativity is a necessary component of ethics and this fact is the primary tool against naturalistic theories of ethics (since naturalism more generally concerns only description as opposed to prescription).
Subjectivism. The view that the truth of moral statements is relative to the individual. Surprisingly common among college freshmen across the country, subjectivism is self-refuting because its maxim, “There are no universal truths,” is itself taken to be a universal truth by the theory. Careful revisions of the the theory’s maxim which avoid obvious refutation tend not to be convincing because they are ad hoc in nature (that is to say, there is no real reason to accept them besides a desire to preserve the theory at hand).