This would explain why Paul Bunyan 's last name is `` Bunyan '' , because `` Bunyan '' sounds like the French-Canadian slang word `` Bonyenne '' , which is something that they might say when they are surprised , like how people who speak English might say `` Good Grief '' or `` My Goodness '' . This would probably explain the origin of Bunyan 's last name since `` Bonyenne '' is a colloquial French-Canadian expression of surprise and astonishment meaning `` Good Grief '' or `` My Goodness '' .