noun pl. mediums -·di·ums or media -·dia (-ə)

1. 1. something intermediate
   2. a middle state or degree; mean
2. an intervening thing through which a force acts or an effect is produced copper is a good medium for conducting heat
3. pl. media me′dia any means, agency, or instrumentality; specif., a means of communication that reaches the general public and carries advertising: in this specif. sense, a singular form media (pl.medias) is now often used
4. any surrounding or pervading substance in which bodies exist or move
5. environment
6. a sterilized nutritive mixture, as enriched agar, for cultivating bacteria, viruses, etc.
7. pl. mediums me′di·ums☆ a person through whom communications are thought to be sent to the living from spirits of the dead
8. any material or technique as used for expression or delineation in art
9. a liquid mixed with pigments to give smoothness

Etymology: L, the middle, neut. of medius: see mid

adjective

1. in a middle position; intermediate in quality, amount, degree, size, etc.
2. neither rare nor well-done: said of cooked meat