phototactic

adjective

pho·​to·​tac·​tic ˌfō-tō-ˈtak-tik How to pronounce phototactic (audio)
: of, relating to, or exhibiting phototaxis
phototactically
ˌfō-tō-ˈtak-ti-kə-lē How to pronounce phototactic (audio)
adverb

Word History

Etymology

International Scientific Vocabulary

First Known Use

1882, in the meaning defined above

Time Traveler
The first known use of phototactic was in 1882

Rhymes for phototactic

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Browse Nearby Words

photosystem
phototactic
phototaxis
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Cite this Entry

“Phototactic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phototactic. Accessed 6 Jul. 2026.

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Medical Definition

phototactic

adjective
pho·​to·​tac·​tic ˌfōt-ō-ˈtak-tik How to pronounce phototactic (audio)
: of, relating to, or exhibiting phototaxis
phototactically
-ti-kə-lē How to pronounce phototactic (audio)
adverb
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