Showing results for "algae"

• plural of alga.

algae

American  

[al-jee] / ˈæl dʒi /

plural noun

• alga
  singular

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 /

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

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Etymology

Origin of algae

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

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Compare meaning

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

• algae vs. seaweed

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Explanation

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.

Example Sentences

See Examples For:

algae alga

During droughts, algae blooms have turned waterways bright green.

From Los Angeles Times ● Oct. 30, 2026

The five-term senator said the categories of products receiving exemptions include corrugated paper cartons, plastic boxes, plastic bags, refrigeration and freezing equipment, packing and wrapping machinery, and seaweed and algae products.

From MarketWatch ● Oct. 23, 2026

The toxic algae is actually cyanobacteria rather than a true algae and can increase dramatically in heat, making people and animals sick when ingested.

From BBC ● Oct. 23, 2026

Overfishing is also hurting corals as certain herbivores and predators help control algae and maintain an ecological balance, the organisation said.

From Barron's ● Oct. 22, 2026

I can see houses beyond, and the lake to one side, the top of it green with algae.

From "All The Bright Places" by Jennifer Niven

This movement of charged particles sends a signal inside the alga that helps it swim.

From Science Daily ● Oct. 19, 2026

You may never have heard of this single-celled alga, but sailors and fishermen know its effect very well: the P. lunula algae are the organisms that occasionally make the see glow blue.

From Science Daily ● Nov. 18, 2024

Blue-green algae is not actually an alga but rather a type of bacteria called cyanobacteria.

From BBC ● Jul. 10, 2023

In the case of Gracilaria, however, things are more complicated: The female alga doesn’t release its egg cells, but keeps them inside funnel-shaped filaments.

From Science Magazine ● Jul. 27, 2022

She is curious; she wants to know the difference between an alga and a lichen, a Diplodon char- ruanus and a Diplodon delodontus.

From "All the Light We Cannot See" by Anthony Doerr

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Related Words

• seaweed

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