Origin: bef. 900; ME, OE
middel; c. G
mittel; akin to ON
methal among.
See mid 1 
Synonyms:
1. equidistant, halfway, medial, midway. 7. midpoint. Middle, center, midst indicate something from which two or more other things are (approximately or exactly) equally distant. Middle denotes, literally or figuratively, the point or part equidistant from or intermediate between extremes or limits in space or in time: the middle of a road. Center, a more precise word, is ordinarily applied to a point within circular, globular, or regular bodies, or wherever a similar exactness appears to exist: the center of the earth; it may also be used metaphorically (still suggesting the core of a sphere): center of interest. Midst usually suggests that a person or thing is closely surrounded or encompassed on all sides, esp. by that which is thick or dense: the midst of a storm.
Antonyms:
1. extreme. 7. extremity.