from The American Heritage® Dictionary of the English Language, 4th Edition
- n. One who stubbornly adheres to outmoded or discredited ideas: "If you don't accept the ideas derived from Adam Smith ... then you are [considered] a flat-earther” ( James Fallows).
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A person who believes or advocates the theory that the earth is flat.
- n. A person who believes or advocates an outlandish, discredited theory; a person who refuses to acknowledge the truth despite overwhelming evidence.
From the long-discredited belief that the earth is flat.(American Heritage® Dictionary of the English Language, Fourth Edition)