What is the meaning of Metamaterial?

Any material engineered to have a property that is rarely observed in naturally occurring materials; especially:

  1. Any material that obtains its electromagnetic properties from its structure rather than from its chemical composition; especially a material engineered to have features of a size less than that of the wavelength of a class of electromagnetic radiation.

Any material that obtains its electromagnetic properties from its structure rather than from its chemical composition; especially a material engineered to have features of a size less than that of the wavelength of a class of electromagnetic radiation.

metamaterial

Source: wiktionary.org