A Fungus fizz was a type of Ferengi beverage, named for a derivation of fungus lifeform. Chek helped himself to a fungus fizz from the bar of a nagal aircar while waiting to talk with Quark about his plan to bring down Grand Nagus Rom in 2376. (DS9 - Worlds of Star Trek: Deep Space Nine novel: Ferenginar: Satisfaction is Not Guaranteed)