tonus

from WordNet (r) 3.0 (2006)

tonus
    n 1: the elastic tension of living muscles, arteries, etc. that
         facilitate response to stimuli; "the doctor tested my
         tonicity" [syn: {tonicity}, {tonus}, {tone}] [ant:
         {amyotonia}, {atonia}, {atonicity}, {atony}]

from The Collaborative International Dictionary of English v.0.48

Tonus \To"nus\, n. [L. a sound, tone. See {Tone}.] (Physiol.)
   Tonicity, or tone; as, muscular tonus.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

22 Moby Thesaurus words for "tonus":
      adaptability, bounce, bounciness, buoyance, buoyancy, elasticity,
      extensibility, flexibility, give, liveliness, rebound, resilience,
      resiliency, responsiveness, snap, spring, springiness, stretch,
      stretchability, stretchiness, tone, tonicity

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