The term "otaku" seems to have been introduced to anime fans in the US and other countries via Studio Gainax's "Otaku no Video 1985," a self-parody film.
Otaku, meaning probably "venerable house," refers to someone who has a devotion to a subject or hobby (not necessarily anime) to the point of not leaving home. For instance, an otaku fan of a particular movie star could quite possibly know all of the films s/he has been in, their birth date, time of birth, shoe size, favorite toothpaste, etc. Generally speaking, calling someone an otaku in Japan is an insult, implying that their social skills have atrophied or never even developed, due to their manic involvement in their chosen fandom.

In America, the term is used to denote a zealous fan, usually of anime and/or manga. Due to its introduction to most people's vocabulary through its tongue-in-cheek use in Gainax's film, "otaku" tends to have a much less dire definition overseas.

When dealing with Japanese people, however, it may be best to keep in mind the modern Japanese image of an otaku -- Someone who only leaves their home to eat or shop, if at all, with an overwhelming and unhealthy obsession about something. It can as easily refer to a stalker or sociopath as it can to a harmless anime buff.

Best to avoid the word altogether if one is not sure of the context in which it will be received.
Positive: "Oh, wow! Check it out: Neck-through, Floyd Rose locking tremolo and an optional push/pull coil tap!" (slaps forehead and laughs) "Man, I am such a guitar otaku, aren't I?"

Negative: "Stay clear of Toshi, man. He's such a RQ otaku, always online. Bet he's never actually even talked to a real-live girl before... You never know when he's gonna' snap, right?"
by Cobweb February 23, 2005
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In it's current, "Americanized" context: Social parasites. Usually fat, white Americans (with some exceptions) who, for whatever reason (unclear even to themselves), have chosen to become Japanese Nationalists based on their preconcieved notions of a non-existent Japanese utopia-- Notions which are developed from a lack of socialization and over-exposure to (mostly fantasy-oriented) Japanese animation (i.e., Anime, i.e., cartoons-- FROM JAPAN!)
Honesty is a bitch, huh?
Otaku: "DESU! POCKY! RAMEN! DURRRR!"
by Escapism Rots Your Brain August 29, 2008
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Otaku is a person (typically male) who has absolutely no social life. Thus an otaku may sits around playing World of Warcraft, trading Dungeons and Dragons cards, watching Japanese animations, and jerking off while relishing pornographic material when he is alone. An otaku will be proud of, and will boast about his mighty forearm that developed over the many years of "over-masturbation".
Whilst leading a life of this sort, an Otaku will complain that no girls are willing to give him pussy.
WHYYYYY?????????????? Strange isn't it?
"Fuck, that otaku left cum stains on my sailor moon comic book!!"

"That guy's such an otaku. He plays WoW all day long and goes for a wank before sleeping."
by The Wok April 13, 2008
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A person who is maniacal about anime, manga, hentai, and various other related paraphernalia such as toys, figures, etc. Include but not limited to Kapil and Suban.
"No one knows why otakus exist, since it is clear they do not mate."
by Golimar December 28, 2007
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Otaku is the Nihonjin (Japanese) word for Home. So an Otaku is Someone who prefers to stay at home, feeding their face w/ Poki and chatting, as opposed to going out and getting laid. Charicterized by their chubby (Fat ass) Appearence and untidy greasy hair, and bad hygene. Someone who'd rather get the dvd collection of Case closed, than buy new clothes. (You if you bothered to look this up)
"I'm an Otaku! Kawaiiiiiii!"

"Dude, you're such an otaku..."
by Hentaihentaiboy October 31, 2006
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in western culture, a person whos obsessed with some form of japanese culture (usually anime-related) (correct me if im wrong)
ANIME OTAKUS KNOW THAT ITS NEGATIVE IN JAPANESE! >.<* its like saying to someone i have no life...hahaha...
by FREAK February 03, 2004
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Japanese for "zealot" or "fanatic". Most common with those who are fanatics of popular (dubbed) anime shows. It is also used to describe said fanatics who go to the point of imitating EVERYTHING that relates to Japanese culture.
When going to college, beware of the otaku nerds who will rant about which episode of Pokemon or Dragonball-Z was better.
by AYB February 10, 2003
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1. An American term that is used to denote a zealous fan, usually of anime,manga and video games.

2. Refers to someone who has a devotion to a subject or hobby (not necessarily anime) to the point of not leaving home.

3. Some one who social skills have atrophied or never even developed, due to their manic involvement in their chosen fandom.
That kid is so Øtakü. He won't leave the basement unless it's to eat.
by morepowerr January 10, 2008
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