Definitions for metaethicsˌmɛt əˈɛθ ɪks, ˈmɛt əˌɛθ-
Random House Webster's College Dictionary
met•a•eth•ics*ˌmɛt əˈɛθ ɪks, ˈmɛt əˌɛθ-(n.)
the branch of ethics dealing with the meaning of ethical terms, the nature of moral discourse, and the foundations of morality.
* (usu. with a sing. v.).
Origin of metaethics:
The descriptive study of philosophical ethical systems, especially with regard to their key concepts, techniques of reasoning and analysis, and linguistic conventions.