from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. Movement of a motile organism using the earth's gravity for orientation.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A living creature's ability to move by orienting itself by gravitational forces.

from The Century Dictionary and Cyclopedia

  • n. The orientation or locomotion of cells or of organisms in relation to the direction of the earth (or to gravity).


Sorry, no etymologies found.



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