Ever walk in the ocean and feel your feet slipping and sliding along the rocks? That slimy green stuff under your feet is algae, a nonflowering plant that grows in the water and has no stems, roots, or leaves.

Algae is actually the plural form of the word alga, which in Latin means, you guessed it: "seaweed." Algae isn't just something gross looking floating on the water. It's actually important in aquatic ecology because the tiny organisms that live suspended in algae are the food base for most marine food chains.

Definitions of algae

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

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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
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
euglenid, euglenoid, euglenophyte
marine and freshwater green or colorless flagellate organism
chlorophyte, green algae
algae that are clear green in color; often growing on wet ricks or damp wood or the surface of stagnant water
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
cryptomonad, cryptophyte
common in fresh and salt water appearing along the shore as algal blooms
an edible seaweed with a mild flavor
dried seaweed especially that cast ashore
any of various seaweeds that grow underwater in shallow beds
sea wrack, wrack
growth of marine vegetation especially of the large forms such as rockweeds and kelp
any of various algae of the genus Tribonema; algae with branching filaments that form scum in still or stagnant fresh water
large brown seaweeds having fluted leathery fronds
sea tang, tang
any of various coarse seaweeds
fucoid, fucoid algae
any of various algae of the family Fucaceae
coarse brown seaweed growing on rocks exposed at low tide
Fucus serratus, serrated wrack, tang
brown algae seaweed with serrated edges
Sargassum bacciferum, gulfweed, sargasso, sargassum
brown algae with rounded bladders forming dense floating masses in tropical Atlantic waters as in the Sargasso Sea
laver, sea lettuce
seaweed with edible translucent crinkly green fronds
pond scum
free-floating freshwater green algae
freshwater algae consisting of minute filaments containing spiral chlorophyll bands
any of various submerged aquatic algae of the genus Chara having nodes with whorled filamentlike branches; usually encrusted with calcium carbonate deposits
freshwater green algae
sea moss
any of various red algae having graceful rose to purple fronds (e.g. dulse or carrageen)
Chondrus crispus, Irish moss, carageen, carrageen, carragheen
dark purple edible seaweed of the Atlantic coasts of Europe and North America
Rhodymenia palmata, dulse
coarse edible red seaweed
laver, red laver
edible red seaweeds
Type of:
any of the unicellular protists

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