Someone who is call a gittychicken is someone who is being very happy while showing signs of nervousness. Being happy while exhibiting behavior associated with not thinking clearly. One who is a gittychicken often excessively smiles and acts silly while also being cowardice as a someone called a "chicken" would be portraying.
"Look at that gittychicken, they're hilarious but they coward away from their own self embarrassment."
Nickname given to bales of marijuana thrown overboard or out of airplanes. Origin is reportedly from members of the US Coast Guard in the area of Southern Florida.