medial

adj. in the middle; of medium size or average dimensions; of or pertaining to the average

n. letter or group of letters in the middle of a word; sound in the middle of a word; voiced stop (Phonetics)

This article is about medial in mathematics. For other uses, see medial (disambiguation). In abstract algebra, a medial magma (or medial groupoid) is a set with a binary operation which satisfies the identity, or more simply, using the convention that juxtaposition has higher precedence. This identity has been variously called medial, abelian, alternation, transposition, bi-commutative, bisymmetric, surcommutative, entropic, etc.Any commutative semigroup is a medial magma, and a medial magma has an identity element if and only if it is a commutative monoid. An elementary example of a nonassociative medial quasigroup can be constructed as follows: take an abelian group (written additively) and define a new operation by x * y = (− x) + (− y).
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Adjective
1. dividing an animal into right and left halves
(synonym) median
(similar) mesial
2. relating to or situated in or extending toward the middle
(synonym) median
(similar) central

adj. mediumistic, of a medium; pertaining to a person who acts as an agent between the world of the living and the world of the dead in spiritual seances (Spiritual)

adj. median, average, mean; located in the middle