What does the term "nigger" refer to in To Kill a Mockingbird? Is is race or class and how do you know?

The term "nigger", as used in To Kill a
Mockingbird, represents the stereotypical thought of the people of the South
during this time period.

While this term today represents a
derogatory name, it did not originate in this fashion. The term originated as a
description of skin color for slaves brought over to America. The term Negro comes from
the Spanish word 'negro'-which means black.  Like many words over time, the word (and
the meaning of the word) has changed.

Today, the term
(depending on whom you are talking to) represents many different things-from terms of
endearment (black to black) to a hated and controversial insult (white to
black).

As for the historical relevance in the novel,
To Kill a Mockingbird was written in 1960. Set in Alabama, the
novel took place in an area of the country where segregation was still prominent, so it
was used as a racial term. Blacks were just beginning to search out for their own
personal rights (Civil Rights Movement; 1954 Brown vs Board of
Education; and 1955 Montgomery Bus Boycott through the acceptance of the 14th
Amendment in 1964). This being said, the novel was placed in a point in American society
where blacks were still looked at as secondary citizens not having the rights as
whites.

Therefore, the word "nigger" was simply Harper
Lee's adherence to the standards seen by the setting of the novel. By including this
word in the text, Lee is able to show a historically valid use of the word. She is also
able to show the change in mentality, by whites, through the use of Atticus' character
and what he teaches Scout and Jem about acceptance and rights.