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

Aside from potential health harms to humans, the tiny particles could be damaging to algae as well as crop harvests.

From The Wall Street Journal

Its larvae inhabit damp mats of moss and algae along the Antarctic Peninsula.

From Science Daily

The other is microscopic algae that live inside the coral's tissues and use sunlight to produce energy, which feeds the coral.

From Science Daily

When the sea overheats, corals eject the microscopic algae that provides their distinct colour and food source.

From Barron's

Because algae cannot easily use this type of iron, increased delivery did not translate into stronger biological growth.

From Science Daily

Related Words

• seaweed