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to·nus | \ ˈtō-nəs 
\
\Definition of tonus
: tone sense 9b especially : a state of partial contraction characteristic of normal muscle
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More Definitions for tonus
tonus
nounto·nus | \ ˈtō-nəs \
\Medical Definition of tonus
1 : tone sense 2a
2 : a state of partial contraction that is characteristic of normal muscle, is maintained at least in part by a continuous bombardment of motor impulses originating reflexly, and serves to maintain body posture
— called also muscle tone
— compare clonusComments on tonus
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Time Traveler for tonus
The first known use of tonus was in 1876
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