or ac·tin·o·mor·phous

[ak-tin-oh-mawr-fik, ak-tuh-noh-]
  1. Biology. having radial symmetry.
  2. Botany. (of certain flowers, as the buttercup) divisible vertically into similar halves by each of a number of planes passing through the axis.

Origin of actinomorphic

First recorded in 1895–1900; actino- + -morphic
Related formsac·tin·o·mor·phy, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for actinomorphic



  1. botany (esp of a flower) having radial symmetry, as buttercupsSee also zygomorphic
Derived Formsactinomorphy, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

actinomorphic in Science


  1. Relating to a flower that can be divided into equal halves along any diameter; radially symmetrical. The flowers of the rose and tulip are actinomorphic. Compare zygomorphic.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.