The word bigot, as defined by Merriam-Webster means a person who is obstinately or intolerantly devoted to his or her own opinions and prejudices; one who regards or treats the members of a group (as a racial or ethnic group) with hatred and intolerance.
An excerpt from The Atlantic's article called 'Bigoted' Is Bigoted: 11 Common Words and Phrases That Started as Slurs, explains:
While a lot of contention surrounds the etymology of this word, no matter which way you spin it, all of the most popular theories come down to some serious violations of PC standards. The first version of name-calling was doled out by 12th-century Frenchmen, who used the derogatory term bigot to describe Normans who wouldn't get off their high horses to kiss the king's feet because of a religious oath they took, which sounded something like "bi God." In French, bigot still means "religious zealot."
A second theory speculates that bigot comes from the Spanish hombre de bigotes, "a man with a mustache," referring to mustachioed Spanish men intolerant of their Jewish neighbors who refused to shave their facial hair for religious reasons.
Trending Now: At a rally in Jackson, Miss., Republican presidential nominee Donald Trump called Democratic foe Hillary Clinton a "bigot" and said that she would do "nothing" for African Americans and Hispanics. Get more scoop from The Washington Post.