• Webster's Revised Unabridged Dictionary
    • Metamerism (Chem) The state or quality of being metameric; isomerism due to different bonding patterns in two substances having the same molecular formula. Contrasted with steroisomerism or optical isomerism. Also, the relation or condition of metameric compounds.
    • Metamerism (Biol) The symmetry of a metameric structure; serial symmetry; the state of being made up of metameres.
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Century Dictionary and Cyclopedia
    • n metamerism In chem., a form of isomerism, that property of certain compound bodies by which they have the same chemical elements combined in the same proportion and with the same molecular weight, while differingin chemical properties. Thus, aldehyde and ethylene oxid have their elements in the same proportion, C2H4O, and the same molecular weight, 44, but are very different in their chemical properties. Two metameric bodies do not, however, belong to the same class or series of compounds. See isomerism, polymerism.
    • n metamerism In zoology, a metameric condition; the state of being metameric; segmentation of the body of an animal along the primary or longitudinal axis, resulting in a series of more or less similar consecutive parts which are serially homologous. See metamere, antimere.
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Chambers's Twentieth Century Dictionary
    • n Metamerism met′a-me-rizm (chem.) a particular form of isomerism, seen in substances having the same molecular formula, but in which all the atoms in the molecule are not directly united:
    • n Metamerism met′a-me-rizm (zool.) segmentation of the body of an animal along the primary axis, producing a series of homologous parts
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Chambers's Twentieth Century Dictionary
Gr. meta, after, meros, a part.


In literature:

One bead, one carriage, one vertebra, would be a metamere.
"Text Book of Biology, Part 1: Vertebrata" by H. G. Wells
Metameric: made up of segments or metameres.
"Explanation of Terms Used in Entomology" by John. B. Smith
The only other example which we have of this metamerism in the Mollusca is presented by the Chitons.
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 6" by Various
It is important to notice that the metameric plan of growth of Chaetopods is still preserved.
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 7" by Various
Each such "mere" is often called a "metamere.
"Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 6" by Various
Remarkable for the adhesion of incomplete fission-products in a metameric series.
"Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 5" by Various