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incomplete flower

noun

a flower without one or more of the normal parts, as carpels, sepals, petals, pistils, or stamens.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
incomplete flower in Science

incomplete flower

A flower lacking one or more of the four parts found in a complete flower: sepals, petals, stamens, and pistils. Compare complete flower. See also imperfect flower.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.