To understand this term it's good to know what the individual words mean in the context that they are in.

Yaoi is the Japanese word for male homosexuality. Put simply it means "gay". The word is actually an acronym that comes from the Japanese phrase, "YAma nashi, Ochi nashi, Imi nashi." meaning no climax, no point, no meaning. Yaoi has also come to describe a particular genre of Japanese shows (anime) and comics (manga) that depict male homosexual relationships. These types of shows are becoming increasingly popular among (mostly) female fans of anime and manga. Fans of yaoi often take their favorite male characters, from any anime or manga, and pair them together (regardless of sexual orientation in the original story).

The second word, lemon, is a term used amongst the fanifiction community. Quite frankly it means that there will be a graphic sex scene in any story designated as a lemon. These types of stories would be ratedp either NC-17 or X by the MPAA. Usually authors will inform the reader of any lemons at the beginning of a story. Lemons refer to any type of sexual activity that includes penetration of some sort. Another term that is used alongside lemon is "lime". This is simply a less graphic description of sexual acts. These stories usually do not go further than heavy petting. Lime's are also more commonly referred to as "shonen-ai" meaning boy's love in Japanese.

So if we combine the two words the meaning is: a story that graphically describes the sexual acts of two male participants whose characters usually come from Japanese anime of manga. Typically these types of stories focus completely on the sex scenes and consist of little-to-no actual plot.
A yaoi lime: "Sasuke grabbed Naruto and desperately pressed his lips against the other boy. He could already feel himself growing excited and began to grind against Naruto."

A yaoi lemon: "Sasuke quickly shoved his cock into Naruto's ass hitting the fox boy's prostate and making him moan."

by combo_bass January 25, 2007
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1. A girl who is absolutely obsessed with yaoi, and usually shonen ai as well. Most (but not all) yaoi fangirls are into anime/manga, and can be at any age (Don't think that just because they're 13 they don't understand buttsecks!)

2. A girl who will go nuts over two extremely hot/cute guys together and is always ready to claw out some poor fellow's eyes if they disrespect their favorite pair (EX: LxLight, RikuxSora, SasuNaru, ect.)
Yaoi fangirl: OMG OMG OMG I LOVE THIS NEW PAIRING!!!

Random guy: Ughhh gross

Yaoi fangirl: SHADDUP!!! >.<
by Skitskat W. July 18, 2010
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when an anime fan girl is so obsessed with male on male love anime, it is almost disturbing. and it's disturbing factor goes through the damned roof when she starts pairing her irl male friends with each other.
oh, liz is such a yaoi queen. she paired me and josh earlier
by the_yuri_king 6969 December 8, 2015
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A subcategory of fangirl.

1. A fangirl who is obsessed with yaoi

2. The female equivalent of the male unbathed fanboy

Beware of yaoi fangirl groups. If one happens to enter the vicinity of a yaoi fangirl, and one is a relatively cute looking guy, run. Run very far, and very fast. Do not look back. Do not mention certain shows with disdain around them. One will be clawed, or at the very least, never seen from again. Examples of these shows would be, Weiß kreuz, Saiyuki, and Inu Yasha. (Don't ask me about the last one, I have no idea why either).

Any anime fangirl could be a yaoi fangirl as they do look like any typical anime fangirl. In fact, if she is into anime, and considers herself a fangirl, there is a very good chance she is a yaoi fangirl. So just beware of them all.

If treaded around carefully, one will survive an encounter with a yaoi fangirl with relatively few scars...that are physical. Psychologists should be standing by.
That yaoi fangirl scared the living crap out of me.

I couldn't hear myself think over the screams of "Seki-san" from those damn yaoi fangirls!
by Ken Hidaka March 8, 2005
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Usually refers to an anime/manga character that appears to be female to the eyes of the audience, but ends up being a male character.
Man, those twin characters are male. I'm telling you. It has yaoi trap written all over it!
by BrownBear August 13, 2006
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A girl who is obsessed with the "yaoi" form of anime. Generally a loving and open person who readily *glomps* or *huggles*

Some are vicious porn frieks, but most are quite personable.
Katya, a.k.a. Queen of the Yaoi Fangirls, can be quite cute, but also vicious if you get between her and her pr0n.
by Zeta Gundam March 12, 2005
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A moment occuring, usually during a movie, in which 2 guys hint at the possibility that they like each other. This gives girls hope that they will get to see some hot guy on guy action.
Girl 1: omg did you see the way he looked into his eyes? Girl 2: yess!! Total yaoi moment!
by kurtsie-girl July 20, 2010
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