A Kanye-ism is something ignorant, stupid and self indulgent that that Kanye West says or does thats makes him look even even more stupid than he already is. Kanye West thinks that he is a word smith and God's gift to the world when he really is God way of showing us that acting like Kanye makes you a egotistical douche-bag prick that people make fun of.
well first and foremost Kanye has recently released a book entitled "thank you and you're welcome", come on, seriously how narcissistic can someone be. Saying thank you and you're welcome implies that he has done something to be thanked for, and the only thing i can think of that he should be thanked for is setting an all time low for douchyness, so that any time someone says " your the biggest douche in the world" you can say "no Kanye is."
Another example of a Kanye-isms is when Kanye said "Imma let you finish" to Taylor swift, he clearly didn't let her finish cause he interrupted her and ruined her evening, and now permanently has the word asshole written across his forehead. He also has given him self the title as the best song writer, and has called him self a song voice for and entire generation. I know those are things south park said about him but he basically said all those things and more.