Social deixis is reference to the social characteristics of, or distinctions between, the participants or referents in a speech event.
The distinction, found in many Indo-European languages, between familiar and polite second person pronouns is an expression of social deixis.
Levinson, Stephen C. 1983.Pragmatics. Cambridge, England: Cambridge University.
Fillmore, Charles J. 1975.Santa Cruz lectures on deixis: 1971. Bloomington, IN: Indiana University Linguistics Club.