The program on Cartoon Network that lists new episodes. The announcer dude on Cartoon Network would say "new episodes on Har Har Tharsdays". That is what it is. Now for the way to use it: You must use it after a joke and it is silent. You may also use this if you said a joke and people dont think it was funny, then you just say it to make people actually laugh. This is funny because Har Har Tharsdays is on cartoon network and pulling something out of your crap makes it hilarious as hell. or you could just say it out of random.
Example 1:
Kelvin: LOL omfg district 9 was so crazy.
Panda: k...?
Kelvin: wow you're a fag.
Panda: Har Har Tharsdays

Example 2:

Hinson: har har tharsdays
Kelvin: dude why the hell do you say it out of random, thats so gay dude.
Panda: yeah man stop copying our words man seriously.
Hinson: har har tharsdays <----WTF?

Example 3:
Panda: so like i was walking down the street and i saw this big fat dude that was fatter than fat albert!!!
Some hot chick: mhm..? and whys that funny?
Panda: idk. HAR HAR THARSDAYS!
Some hot chick: LOL YOU'RE SO CUTE PANDA BOY <3
by pandaboyxxx September 7, 2009
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