allotropism

noun Chemistry.

1. a property of certain elements, as carbon, sulfur, and phosphorus, of existing in two or more distinct forms; allomorphism.

noun

1. the existence of an element in two or more physical forms. The most common elements having this property are carbon, sulphur, and phosphorus

n.

1. The existence of two or more forms of an element that differ from one another in crystalline or molecular structure.