phototonus

noun
pho·​tot·​o·​nus | \ fōˈtätᵊnəs \

Definition of phototonus

: 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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History and Etymology for phototonus

New Latin, from phot- + tonus

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Cite this Entry

“Phototonus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phototonus. Accessed 4 Dec. 2020.

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