I take the term to mean those who believe that he is ineligible BECAUSE he was born in Kenya. These are the ones I believe have missed the point.
If you want to include those who believe he is ineligible because he was born in America and his father was not a US Citizen, thus he is not "Natural Born", then my comment regarding "Birther's" would exclude the second group.
I define it as a derogatory term invented by certain American fascists in order to demonize those patriots who simply want the truth regarding his eligibility.
Even Socialist Bernie Sanders knew it required two citizen parents.
I don't know nor care where he was born, but I doubt there is a real birth certificate with his name on it.