A word spoken by Ms. Garrison in LesBos, the lesbian bar that was almost taken over by Persians in South Park (episode D-Yikes!).
Also spelled les-tastic.
The greatest pleasure that one can experience while on the World Wide Web. Go to google and type in Zentastic Penis Gross and experience the revolution!
Johnny: Yo, I just saw Zentastic last night and I have a whole new outlook on life.
Billy: You're a fag.