A derogatory word used to label people with red hair. similar to calling blacks niggers, chinese people chinks, and japanese people gooks. Also a sign of a lack of creativity or a need to be a part of a group. People that yell arps tend to be drug addicts that rape women in dark alleys.
all the girls knew he was a dickhead when he yelled the word arps, because they knew that all guys with red hair have huge wangs.