polymorphism noun. 
[pɒlɪ'mɔ:fɪz(ǝ)m] M19.[formed as POLYMORPHOUS + -ISM.]Polymorphous character or condition; the occurrence of something in several different forms; 
Chemistry & 
Mineralogy the occurrence of polymorphs. Also, an instance of this. 
 [TahlilGaran] English Dictionary ▲