Definition of "quillwort" [quill•wort]

• Any of several vascular, spore-bearing, aquatic or marsh plants of the genus Isoetes having short rhizomes and quill-like leaves. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Botanists are not yet quite certain about the seed-cases of this tree, but Mr. Carruthers believes that they grew inside the base of the leaves, as they do in the quillwort, a small plant which grows at the bottom of our mountain lakes."
• "Coastal plant life abounds: rock samphire, greater sea spurrey, rare ferns like the primitive quillwort, and multiple strange and beautiful lichens unseen on the continent."
• "African yam and an ancient quillwort from a small rockpool in Namaqualand are among the 250 new plant species discovered internationally by botanists"
• "Cape Town - An unusual metre-high South African yam and an ancient quillwort from a small rock pool in Namaqualand are among the 250 new plant species discovered internationally by botanists from the renowned Royal Botanic Gardens in Kew this year."