A disorder characterized by one having the affinity to give too many overly-tackyholiday cards.
The last 3 Christmases, Jon sent me and everyone in the family a card which was composed of little more than the words "Ho,Ho,Ho." It is apparent that he suffers from tackycardia.
Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults.
When you're hospitalized and hooked up to a heart monitor and start jacking off and your heart rate rises to the point where hospital staff is called in thinking you're having a cardiac event only to discover you're just jacking off. A portmanteau of jacking off and tachycardia.
I had to check up on the patient because his heart rate was through the roof but it turned out to just be jackycardia.