“A professor of history at the university in Chapel Hill believes [Tar Heel] should be two words….and he has been campaigning quietly to get the matter corrected and standardized….
“William Powell has petitioned Merriam-Webster… whose definition in Webster’s Third Unabridged Dictionary reads: ‘tarheel, also tarheeler: from Tarheel State, nickname for North Carolina; a North Carolinian — a nickname.’
“Frederick Mish, joint editorial director for Merriam-Webster, says the spelling as one word is not likely to change for a while.
” ‘We have to weigh evidence from North Carolina as well as evidence from other places. There has to be a clear-cut preponderance one way or another as to spelling….'”
— From “Tarheel or Tar Heel?” by the Associated Press in the Wilmington Star-News (Dec. 11, 1977)
However long it took Merriam-Webster to find its requisite “clear-cut preponderance,” today the online Unabridged refers to “Tar Heel or Tarheel also Tarheeler.”
“Tarheeler”? A topic for another day….