middle

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Equally distant from extremes or limits; central.
• adjective Being at neither one extreme nor the other, as of a sequence or scale; intermediate.
• adjective Of or relating to a division of geologic time between an earlier and a later division.
• adjective Of or relating to a stage in the development of a language or literature between earlier and later stages.
• adjective Grammar Of, relating to, or being a verb form or voice in which the subject both performs and is affected by the action specified.
• noun An area or a point equidistant between extremes; a center.
• noun Something intermediate between extremes.
• noun The middle part of the human body; the waist.
• noun Logic A middle term.
• noun The middle voice.
• noun A verb form in the middle voice.
• transitive verb To place in the middle.
• transitive verb Nautical To fold in the middle.
• idiom (in the middle) In a difficult situation.
• idiom (in the middle) Engaged in doing something.

from The Century Dictionary.

• Equally distant from the extremes or limits; mean; middling: as, the middle point of a line; the middle time of life.
• Intervening; intermediate.
• In grammar: Intermediale between active and passive: applied to a body of verb-forms of which the office is more or less distinctly reflexive, or denotes the subject as acting on or for or with reference to itself, often answering to an English intransitive verb: as, middle voice, middle ending, middle tense.
• Intermediate between smooth (unaspirated) and rough (aspirated): as, a middle (medial) mute. See mute, n
• Nautical, a shallow place, as a bank or bar.
• noun The point or part equally distant from the extremities, limits, of extremes; a mean.
• noun Specifically, the middle part of the human body; the waist.
• noun An intervening point or part in space, time, or arrangement; something intermediate.
• noun In logic, same as middle term.
• noun In grammar, same as middle voice. See I., 3.
• noun Synonyms Center, Midst, Middle. Center is a precise word, ordinarily applied to circular, globular, or regular bodies: as, the center of a circle, globe, field; but it is used wherever a similar exactness appears to exist: as, the center of a crowd. Midst regards the person or thing as enveloped or surrounded on all sides, especially by that which is close upon him or it, thick or dense: as, in the midst of the forest, the waves, troubles, one's thoughts. Except as thus modified by the idea of envelopment or close environment, the old idea of midst as meaning the middle point (see Gen. i. 6; Josh. vii. 23; 1 Ki. xxii. 35) is quite obsolete. Midst is very often used abstractly or figuratively, center rarely, middle never. Middle is often applied to extent in only-one direction: as, the middle of the street, of a block of houses, of a string; it is often less precise than center: compare the center and the middle of a room.
• To set or place in the middle. Specifically
• In foot-ball, to kick or drive (the ball) into the middle, so that it may be kicked through the goal.
• To balance or compromise.
• To ascertain or mark the middle of (as of a line), by doubling or otherwise; fold in the middle; double, as a rope.

from the GNU version of the Collaborative International Dictionary of English.

• noun The point or part equally distant from the extremities or exterior limits, as of a line, a surface, or a solid; an intervening point or part in space, time, or order of series; the midst; central portion.
• adjective Equally distant from the extreme either of a number of things or of one thing; mean; medial
• adjective Intermediate; intervening.
• adjective the period of time intervening between the decline of the Roman Empire and the revival of letters. Hallam regards it as beginning with the sixth and ending with the fifteenth century.
• adjective in England, people who have an intermediate position between the aristocracy and the artisan class. It includes professional men, bankers, merchants, and small landed proprietors.
• adjective (Paint.) See Middle-ground.
• adjective See English, n., 2.
• adjective China.
• adjective (Chem.) that part of the distillate obtained from coal tar which passes over between 170° and 230° Centigrade; -- distinguished from the light oil, and the heavy oil or dead oil.
• adjective in the slave trade, that part of the Atlantic Ocean between Africa and the West Indies.
• adjective (Arch.) Same as King-post.
• adjective [U.S.] New York, New Jersey, Pennsylvania, and Delaware; which, at the time of the formation of the Union, occupied a middle position between the Eastern States (or New England) and the Southern States.
• adjective (Logic) that term of a syllogism with which the two extremes are separately compared, and by means of which they are brought together in the conclusion.
• adjective (Paint.) a subdued or neutral tint.
• adjective (Gram.) See under Voice.
• adjective the men on watch during that time.
• adjective a pugilist, boxer, or wrestler classed as of medium weight, i. e., over 140 and not over 160 lbs., in distinction from those classed as light weights, heavy weights, etc.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A centre, midpoint