phototonus
[ foh-tot-n-uh s ]
/ foʊˈtɒt n əs /
noun Biology.
the normal condition of sensitiveness to light in organisms or their organs.
the irritability exhibited by cytoplasm when exposed to light of a certain intensity.
Nearby words
Related formspho·to·ton·ic [foh-tuh-ton-ik] /ˌfoʊ təˈtɒn ɪk/, adjective
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British Dictionary definitions for phototonus
phototonus
/ (fəʊˈtɒtənəs) /
noun
the condition of plants that enables them to respond to the stimulus of light
Derived Formsphototonic (ˌfəʊtəʊˈtɒnɪk), adjective
Word Origin for phototonus
C19: from photo- + Greek tonos tone
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Medicine definitions for phototonus
phototonus
[ fō-tŏt′n-əs ]
n.
The state of being sensitive to or irritated by light.
Related formspho′to•ton′ic (fō′tə-tŏn′ĭk) adj.
The American Heritage® Stedman's Medical Dictionary
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