Your rainbow fish is the person who everyone thinks you like but you don't really like. Rainbow fish is for teasing purposes and for confusing people who don't understand what it means. It can become very annoying.
Pheobe: Your rainbow fish is Heston, Izzy!
Izzy: What?! Never. Your rainbow fish is Adam!
Pheobe: Yuck no! Not Adam!
Adam: What am I?
Pheobe and Izzy: Doesn't matter!
Adam: *walks away confused*
Izzy: What?! Never. Your rainbow fish is Adam!
Pheobe: Yuck no! Not Adam!
Adam: What am I?
Pheobe and Izzy: Doesn't matter!
Adam: *walks away confused*
by DeviLs brOther April 15, 2021
Get the Rainbow fishmug. A person who constantly wants or desires friends, significant others, objects of desire, etc. that he or she does not have. When a rainbow chaser finally obtains the friend, significant other, object of desire, etc. that he/she so longed for; the rainbow chaser does not appreciate whatever the subject he/she was seeking and moves on to other desires that are not obtained. Rainbow chasers are never truly happy as they never appreciate anybody or anything. Because they are so selfish and lack commitment, rainbow chasers can be narcissists.
by Major Madcat July 17, 2019
Get the rainbow chasermug. "Dude, seriously you're a frickin rainbow licker, go fuck a guy"
-"He's a beast!"
-"Nahh hes a rainbow licker."
-"He's a beast!"
-"Nahh hes a rainbow licker."
by thecoolestsinceslicedbread April 25, 2010
Get the rainbow lickermug. by bumfuck January 3, 2008
Get the rainbowmug. by Von Meek January 23, 2009
Get the Tasting the Rainbowmug. 
After eating food with copious amounts of food coloring, your poo takes on colors other than the usual shades of brown.
by Tim J Kelly August 12, 2005
Get the shitting the rainbowmug.