Definition one: Somebody whose either losing an argument and needs to create a diversion.

Definition Two: Somebody who has the analytical and decrypting skills of an autistic 6 year old who cannot recognize a routinely based word if it even has a liiitle typo or misplacement that anybody with a brain would so easily recognize. This person is often impossible to communicate with due to the need to spell every single thing perfectly or else they will get confused due to their poor description and analytical skills. Everything taught to them after grade 1 fades out of their mind in no more than 2 minutes. Talking to them is like talking to a wall.
Example one:
Reasonable Human Being 1: wtf you got your dick stuck in a bench and cut it off to escape from it?! ur stupid bro! rlly stupid!
Grammar Nazi : Learn to spell before you call me stupid!
Reasonable Human Being 1: Aha! So you tried to change the topic to grammar because there's no way you can provide a reasonable response to what I have said! You sir are a typicl Grammar Nazi!
Grammar Nazi: Typical*
Reasonable Human Being: Shut up you have no dick. Literally you have no dick you cut it off and this is why you're resorting to being a Grammar Nazi!
*Grammar Nazi blocks the Comprehensible Human being because he/she has no good comebacks*

Example two:

Comprehensible Human Being: why is it that you stare blankly into space for 18 hours a day while chewing on your shirt?
Grammar Nazi: What the hell do you even speak English? Your grammar is atrocious!
Comprehensible Human Being: Any autistic child would be able to recognize what I have just typed....
Grammar Nazi: Oh my god! You put 4 dots! I have no idea what you're trying to say! Learn to speak English please!
Comprehensible Human Being: If your mother dyed her hair black would you still recognize her?
Grammar Nazi: No of course not! Who would be able to recognize such an enormous change?
Comprehensible Human Being: Ah OK I think it's settled. You're just plain retarded.
*Grammar Nazi is chewing shirt while bug eyed*
Comprehensible Human Being: I rest my case.
by Comprehensible Human Being October 22, 2013
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A person who has mastered the art of speaking the English language. They are best known for going on social media and constantly correcting the incorrect usage of other users, and are almost universally hated by everyone. An occasional correction does not signify a Grammar Nazi, that title is earned after months of corrections.

KEEP IN MIND: Many people who are corrected by a Grammar Nazi really need the public shame because they've put too many poorly-written statuses on their social media accounts, and the Grammar Nazi should be hailed as a hero. If the person in question is clearly not a native English speaker, then the Grammar Nazi is the villain
Guy: Grammar Nazis mean us no harm. There simply helping us hone our grammar skills.
Grammar Nazi: *They're
Guy: My mistake. Thank you.
by The most intelligent human November 17, 2016
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Someone who is so educated, they are so inclined to pick out every damn grammatical mistake you make in common conversation, texting, and websites. They make you feel uneducated. Just like Adolf Hitler and the Nazis, they want to control every facet of your grammar and sentence structure. They say "Oh, I'm just trying to help you through constructive criticism.", when they obviously are just calling out mistakes for personal gain.
Teenage Girl: "Oh my ged sharon, i was at the mall the other day and i bumped into sharyl!"
Grammar Nazi: "You misspelled god, didn't capitalize 2 names, and didn't capitalize 2 'I's."
Teenage Girl: "stupid grammer Nazi"
Grammar Nazi: "You misspelled grammar, and didn't capitalize the word beginning the sentence."
Teenage Girl: *clicks out of chatroom because Grammar Nazi won't stop his shit*
by somedude149 April 12, 2014
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N. A person who hates false grammar.

adj. The act of repeatedly correcting another person's grammar.
Hippie: 'Dude, that party was the funnest'
Grammar Nazi: 'You mean: Dude, that party was the most fun.'
by The Friendly Nazi June 3, 2014
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A person so obsessed with grammar that they will go out of their way to correct you.
Fb post: i really shouldnt have done that
Comment: *I really shouldn't have done that.
Reply: really??? correcting my fb posts???
Comment: *Really, you are correcting my facebook posts?
Reply: what are you, a grammar nazi???
by redd menace January 19, 2013
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Usually a pompous arrogent person who uses a screen name such as "sumfacts" or the like, and resorts to grammar correcting when losing a debate in an online forum.
Why are you always correcting everyones post are you the "grammar nazi"?
by TwoSpirit August 20, 2007
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An intelligent person who is prone, by no fault of their own, to correct the grammar of a grammatically incorrectly sentence.
Q: "Where's my keys?"
GN: "'Where ARE my keys,' you dumbass!"
Q: "...You're such a grammar nazi. Asshole."
by Grammar Naziiiiii October 22, 2006
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