true chameleon refers to what i believe is
a prehensile tail, eyes that can move independitly in a almost 360 fashion, aborial adapted feet for grasping branches and finally the ability to instanlty change colors to there emotion or other range of factors that may or may not affect them.
unlike the common anole which has been called a "chameleon" can only adapt to color in order to blend in,even then its color spectrum is still limited to a certain degree.