An aquatic plant (Hydrilla verticillata) native to Eurasia, Africa, and Australia, having whorled, lance-shaped leaves and small white flowers. It is considered a weed in North America, where it forms large dense mats in waterways.
[New Latin, genus name, diminutive of Latin hydra, hydra; see HYDRA.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
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