A total anime addict, who is also a luser
that thinks they are a sysadmin or computer tech simply because they know how to use IRC
to leech their 500 gigs of garbage anime every week while infesting said computer (usually their dad's) with various worms and trojans
in the process.
An otaku REFUSES to have a job unless it involves some connection to anime. An otaku generally has no social life outside of anime as they will break up with any decent girl/boyfriend who is intolerant of their anime addiction. Also, most male otakus have a secret fetish of being female or are gay/bisexual.
Otakus can generally be identified by their suitcase-sized CD/DVD case, filled with 1000+ episodes of d- grade amine series. Naturally, the 1000+ blank disks they're burned on were stolen from dad or a friend, becuase the otaku won't even try to get a job.
Many otakus are now or have been homeless for a year or more, getting kicked out of everywhere every 2 weeks after they are caught stealing CD-R's to burn anime on.
Most are total losers who will never amount to anything more than a homeless statistic, welfare slob or "that kid down the block" who lives above his parent's garage.
"There's no way I will work at Taco Bell. I'm an otaku!"
Tom: "I'm such an otaku! I've got 2458 anime CD's now!"
Bill:"Otaku indeed! You're just a 11 year old moronic kid in a grown man's body!"