noun pho·tot·o·nus \fōˈtätənəs\

Definition of phototonus

  1. :  tonic condition (as of musculature) resulting from exposure to particular conditions of lighting phototonus in plants usually results in curvature towards a source of light

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Origin and Etymology of phototonus

New Latin, from phot- + tonus

Seen and Heard

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to criticize severely

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