Muscle tonus

Definition
noun
(1) The muscle in a steady partially contracted state caused by the successive flow of nerve impulses.
(2) The amount of tension or resistance to movement in a muscle.
Supplement
Muscle tonus helps in maintaining body posture. For instance, the muscles holding the jaw keep it in position with a continuous and partial contraction. When a person sleeps or loses consciousness, the muscle tonus declines.
Word origin: tonus » Greek tónos (tone)
Synonyms:

muscular tonus
muscle tone
residual muscle tension
tonus

See also: hypotonia, hypertonia.

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