(a.) Having the same percentage composition; -- said of two or more different substances which contain the same ingredients in the same proportions by weight, often used with with. specifically: (a) Polymeric; i. e., having the same elements united in the same proportion by weight, but with different molecular weights; as, acetylene and benzine are isomeric (polymeric) with each other in this sense. See Polymeric. (b) Metameric; i. e., having the same elements united in the same proportions by weight, and with the same molecular weight, but which a different structure or arrangement of the ultimate parts; as, ethyl alcohol and methyl ether are isomeric (metameric) with each other in this sense. See Metameric.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). Isomeric. Retrieved September 22, 2026, from http://smartdefine.org/isomeric/definitions/2023986 |
| Chicago | Webster's. 2011. "Isomeric" http://smartdefine.org/isomeric/definitions/2023986 (accessed September 22, 2026). |
| Harvard | Webster's 2011, Isomeric, Smart Define, viewed 22 September, 2026, <http://smartdefine.org/isomeric/definitions/2023986>. |
| MLA | Webster's. "Isomeric" 27 May 2011. Web. 22 September 2026. <http://smartdefine.org/isomeric/definitions/2023986> |