alga

noun

al·​ga ˈal-gə How to pronounce alga (audio)
plural algae ˈal-(ˌ)jē How to pronounce alga (audio) also algas
: a plant or plantlike organism of any of several phyla, divisions, or classes of chiefly aquatic usually chlorophyll-containing nonvascular organisms of polyphyletic origin that usually include the green, yellow-green, brown, and red algae in the eukaryotes and especially formerly the cyanobacteria in the prokaryotes
algal adjective

Example Sentences

Recent Examples on the Web The alga draws energy from sunlight and produces sugars, which the bacterium uses as fuel. Ashley P. Taylor, Discover Magazine, 22 Sep. 2012 This is the first recorded example of an alga practicing an aquatic equivalent to pollination. Jack Tamisiea, Scientific American, 28 July 2022 Yet here in this massive pool swirls more than a million liters of Nannochloropsis, a salt-loving alga that flourishes on the brackish water pumped from below. Amy Nordrum, IEEE Spectrum, 30 May 2018 For example, since the 1960s, scientists have shown that a type of alga shows a daily cycle in its photosynthesis, even without a nucleus. Ed Yong, Discover Magazine, 16 May 2012 In return, the bacterium processes nitrogen gas into ammonium, which the alga needs. Ashley P. Taylor, Discover Magazine, 22 Sep. 2012 Namely, a safe place to hide from predators and a source of food in the form of small, single-celled alga that grow on red seaweed plants, reports Erik Stokstad for Science. Sarah Kuta, Smithsonian Magazine, 29 July 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. Andrew Robinson, Scientific American, 21 July 2022 Lichens are actually two organisms working together: a fungus and either alga or cyanobacterium. Corryn Wetzel, Smithsonian Magazine, 17 Feb. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'alga.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

Etymology

Latin, seaweed

First Known Use

1551, in the meaning defined above

Time Traveler
The first known use of alga was in 1551

Dictionary Entries Near alga

Cite this Entry

“Alga.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alga. Accessed 22 Mar. 2023.

Kids Definition

alga

noun
al·​ga ˈal-gə How to pronounce alga (audio)
plural algae ˈal-(ˌ)jē How to pronounce alga (audio)
: any plant or plantlike organism (as a seaweed) that includes forms mostly growing in water, lacking a system of vessels for carrying fluids, and often having chlorophyll masked by brown or red coloring matter
algal adjective

Medical Definition

alga

noun
al·​ga ˈal-gə How to pronounce alga (audio)
plural algae ˈal-(ˌ)jē How to pronounce alga (audio) also algas
: a plant or plantlike organism of any of several phyla, divisions, or classes of chiefly aquatic usually chlorophyll-containing nonvascular organisms of polyphyletic origin that usually include the green, yellow-green, brown, and red algae in the eukaryotes and especially formerly included the cyanobacteria in the prokaryotes
algal adjective

More from Merriam-Webster on alga

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