n. pl. al·gae (-jē)
Any of numerous photosynthetic organisms of aquatic or moist habitats, ranging in size from single-celled diatoms to large seaweeds such as kelp, and characterized by a lack of complex organs and tissues. Once classified within the plant kingdom, the algae are now considered to include several unrelated groups belonging to different kingdoms.
algal (ălgəl) adj.
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