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tropotaxis

American  
[trop-uh-tak-sis, troh-puh-] / ˌtrɒp əˈtæk sɪs, ˌtroʊ pə- /

noun

Zoology.
  1. straight movement by an organism toward or away from a source of stimulation as a result of comparing information received by paired sensory receptors on both sides of the body.


Etymology

Origin of tropotaxis

First recorded in 1930–35; tropo- + -taxis