algae

American  

[al-jee] / ˈæl dʒi /

plural noun

singular

alga

1. Microbiology. any of numerous groups of chlorophyll-containing, mainly aquatic, eukaryotic organisms ranging from microscopic single-celled forms to multicellular forms 100 feet (30 meters) or more long, distinguished from plants by the absence of true roots, stems, and leaves and by a lack of nonreproductive cells in the reproductive structures: classified into the six phyla Euglenophyta, Crysophyta, Pyrrophyta, Chlorophyta, Phaeophyta, and Rhodophyta.

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algae British  

/ ˈældʒiː, ˈælɡəl /

plural noun

1. unicellular or multicellular organisms formerly classified as plants, occurring in fresh or salt water or moist ground, that have chlorophyll and other pigments but lack true stems, roots, and leaves. Algae, which are now regarded as protoctists, include the seaweeds, diatoms, and spirogyra

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algae Cultural  

1. Primitive organisms that contain chlorophyll but do not have structures, such as xylem and phloem, to transport fluids. Algae sometimes contain only a single cell, and nowadays they are not considered members of the plant kingdom.

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Discover More

Algae supply a considerable part of the world's oxygen.

The most familiar algae are the greenish scum that collects in still water.

Other Word Forms

• algal adjective

Etymology

Origin of algae

First recorded in 1790–1800; from New Latin, plural of Latin alga “seaweed”

Compare meaning

How does algae compare to similar and commonly confused words? Explore the most common comparisons:

• algae vs. seaweed

Example Sentences

Some cichlids evolved into predators, while others specialized in feeding on algae, sifting sand, or consuming plankton.

From Science Daily

Scientists found the best strains of algae, when grown in large outdoor ponds, were producing oil at roughly 6% of Exxon’s stated goal.

From The Wall Street Journal

However, transferring the complex machinery from algae into land plants has proven extremely difficult.

From Science Daily

"I hate any kind of pollution to be honest, there's blue and green algae here, there's bird flu, ducks and swans dying."

From BBC

They develop when algae and microbial communities grow in mats across sandy seafloors.

From Science Daily

Related Words

• seaweed