Any of various tall plants of the Eurasian genus Ferula of the parsley family, having hollow stems, finely divided foliage, and large yellow inflorescences, especially F. communis, whose sturdy dried stalks were used by the ancient Greeks and Romans to make walking sticks and thyrsi. Some giant fennel species are toxic and are noxious weeds on grazing grounds.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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