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

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

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

The broad category also includes organisms such as kelp, slime molds, and red algae, some of which grow into large, complex structures.

From Science Daily ● Oct. 8, 2026

The National Park Service at that time had been working to remove algae that had covered the pool bottom shortly after the renovation work was finished.

From The Wall Street Journal ● Oct. 1, 2026

The lake's extreme briny environment sustains algae blooms that attract flamboyances of pink flamingos that thrive in the area.

From BBC ● Sep. 12, 2026

Shortly after reopening, the water turned green with algae.

From Salon ● Sep. 12, 2026

I tried every­thing but the worms, including the algae.

From "Life of Pi" by Yann Martel

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

The alga could be providing a place for younger isopods to hide from predators, as Idotea is often the same color as the plant.

From Science Magazine ● Jul. 27, 2022

Giant kelp is the common name for Macrocystis pyrifera, a species of alga that grows into lush underwater forests along the coast of the northeastern Pacific Ocean, from Baja California north to southeastern Alaska.

From Scientific American ● Jul. 21, 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

Related Words

• seaweed