Well, he played college football at North Texas State University (now University of North Texas), and their nickname is "Mean Green." So, I would assume that either he got his nickname from that, which would answer the question, or they took on that nickname from him, which would still leave the original question unanswered.
The TCU Horned Frogs is the nickname of the Texas Christian University. Their mascot is a horned frog in reference to the Texas horned lizard which has the scientific name of Phrynosoma cornutum.
The nickname for Texas is, the "Lone Star State"
The state nickname of Texas is The Lone Star State.
The nickname for Princeton University is Old Nassau.
UTSA, or the University of Texas at San Antonio, was established on June 5, 1969. It is a public university and the eighth largest in Texas. The colors are blue and orange and the sport team nickname is the Roadrunners.
The University of Texas. The University of Texas.
1.University of Texas 2.Texas A&M University 3.Baylor University 4.Texas Tech University 4.University of North Texas 5.Texas State University 7.University of Texas at San Antonio
The nickname for Montana State University is the Bobcats.
The nickname for Utah State University is the 'Aggies'.
Tigers is the nickname for the Catholic Georgetown University.