Yeetism is the psychological condition of yeeting at any given moment without warning. People with yeetism often have trouble maintaining relationships and friendships alike, because they keep leaving pretty much habitually. Think commitment issues, but catchier.
Yeetism is a condition that only Florida Men have. The virus can be transmitted through watching memes and saying "yeet". If a subject has this virus, they begin to throw things uncontrollably until their arm muscles decline completely. After the decline of the subject's arm muscles, the rest begin to decline until they die of being paralyzed.
Doctor: Well, I checked you and it seems you have yeetism.