from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. Any of various chiefly aquatic, eukaryotic, photosynthetic organisms, ranging in size from single-celled forms to the giant kelp. Algae were once considered to be plants but are now classified separately because they lack true roots, stems, leaves, and embryos.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. Any of many aquatic photosynthetic organisms, whose size ranges from a single cell to giant kelps and whose form is very diverse; some are eukaryotic and some prokaryotic; includes the seaweeds.

from the GNU version of the Collaborative International Dictionary of English

  • n. A kind of seaweed; pl. the class of cellular cryptogamic plants which includes the black, red, and green seaweeds, as kelp, dulse, sea lettuce, also marine and fresh water confervæ, etc. The algae are primitive chlorophyll-containing mainly aquatic eukaryotic organisms lacking true stems and roots and leaves.

from The Century Dictionary and Cyclopedia

  • n. A cryptogam of the class of Algæ.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. primitive chlorophyll-containing mainly aquatic eukaryotic organisms lacking true stems and roots and leaves


Latin, seaweed.
(American Heritage® Dictionary of the English Language, Fourth Edition)


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