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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.
al′gal (ăl′gəl) adj.
Plural algae (ăl′jē)
Any of various green, red, or brown organisms that grow mostly in water, ranging in size from single cells to large spreading seaweeds. Like plants, algae manufacture their own food through photosynthesis. They form a major component of marine plankton and are often visible as pond scum. Although they were once classified as plants, they do not have roots, stems, or leaves, and are now viewed as protists.
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|Noun||1.||alga - primitive chlorophyll-containing mainly aquatic eukaryotic organisms lacking true stems and roots and leaves|
protoctist - any of the unicellular protists
seaweed - plant growing in the sea, especially marine algae
golden algae - algae having the pigments chlorophyll and carotene and xanthophyll
yellow-green algae - any alga of the division Chrysophyta with its chlorophyll masked by yellow pigment
diatom - microscopic unicellular marine or freshwater colonial alga having cell walls impregnated with silica
confervoid algae - algae resembling confervae especially in having branching filaments
brown algae - algae having the chlorophyll masked by brown and yellow pigments
chlorophyte, green algae - algae that are clear green in color; often growing on wet ricks or damp wood or the surface of stagnant water
chlorella - any alga of the genus Chlorella
red algae - marine algae in which the chlorophyll is masked by a red or purplish pigment; source of agar and carrageenan