The act of really scribbling your pen a lot to see if there's any ink left in it. Often accompanied with shaking the pen in between attempts of the circular (usu) scribbles.
Ralphie was trying to take notes on the important point being made, but was struck by a need of appendeciding.

Once upon a time, Picasso paid for bills with his appendeciding art.
by Leif May 12, 2005
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