METAMERISM
Me*tam"er*ism, n.

1. (Biol.)

Defn: The symmetry of a metameric structure; serial symmetry; the state of being made up of metameres.

2. (Chem.)

Defn: The state or quality of being metameric; also, the relation or condition of metameric compounds.

METAMORPHIC
Met`a*mor"phic, a. Etym: [See Metamorphosis.]

1. Subject to change; changeable; variable.

2. Causing a change of structure.

3. (Geol.)

Defn: Pertaining to, produced by, or exhibiting, certain changes which minerals or rocks may have undergone since their original deposition; — especially applied to the recrystallization which sedimentary rocks have undergone through the influence of heat and pressure, after which they are called metamorphic rocks.