The Collaborative International Dictionary of English v.0.48:

Muscular \Mus"cu*lar\, a. [Cf. F. musculaire. See Muscle.]
   1. Of or pertaining to a muscle, or to a system of muscles;
      consisting of, or constituting, a muscle or muscles; as,
      muscular fiber.
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            Great muscular strength, accompanied by much
            awkwardness.                          --Macaulay.
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   2. Performed by, or dependent on, a muscle or the muscles.
      "The muscular motion." --Arbuthnot.
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   3. Well furnished with muscles; having well-developed
      muscles; brawny; hence, strong; powerful; vigorous; as, a
      muscular body or arm.
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   Muscular Christian, one who believes in a part of religious
      duty to maintain a healthful and vigorous physical state.
      --T. Hughes.

   Muscular Christianity.
      (a) The practice and opinion of those Christians who
          believe that it is a part of religious duty to
          maintain a vigorous condition of the body, and who
          therefore approve of athletic sports and exercises as
          conductive to good health, good morals, and right
          feelings in religious matters. --T. Hughes.
      (b) An active, robust, and cheerful Christian life, as
          opposed to a meditative and gloomy one. --C. Kingsley.

   Muscular excitability (Physiol.), that property in virtue
      of which a muscle shortens, when it is stimulated;
      irritability; contractility.

   Muscular sense (Physiol.), muscular sensibility; the sense
      by which we obtain knowledge of the condition of our
      muscles and to what extent they are contracted, also of
      the position of the various parts of our bodies and the
      resistance offering by external objects.
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