Sometimes abbreviated to "nape", for short.
To be used as a euphemism when one wishes to belittle or mock such caucasians in their presence, without running the risk of being lynched or sodomized.
"No, I do not watch NASCAR, my fine Southern friend, as I am not a scarlet nape."
Upon entering The Boar's Nest bar, Harold and Kumar quickly realized they had entered the domain of the scarlet nape.
As it was Friday night and Lynyrd Skynyrd was in town, the napes were out in force.