RhymeZone: metamerism definitions

Definitions of metamerism:

noun: (biology) The segmentation of the body into similar discrete units.
noun: (psychology) The matching of a perceived attribute between objects with differing physical attributes.
noun: (colorimetry) The matching of apparent color of objects with different spectral power distributions.
noun: (chemistry) Structural isomerism.

(Definitions from Wiktionary)