phy·​lum | \ˈfī-ləm \
plural phyla\ˈfī-​lə \

Definition of phylum 

1a : a direct line of descent within a group

b : a group that constitutes or has the unity of a phylum specifically : a primary category in biological taxonomy especially of animals that ranks above the class and below the kingdom — compare division sense 10

2 : a group of languages related more remotely than those of a family or stock

Examples of phylum in a Sentence

Recent Examples on the Web

Looking to classify their animals into a phylum, Hoyal Cuthill and Han ran a computer analysis using anatomical features to reconstruct evolutionary relationships. David Grossman, Popular Mechanics, "Weird Prehistoric Plant Turns Out To Be Weird Prehistoric Animal," 8 Aug. 2018 And a new phylum is just what Higgins and Kristensen had on the lab table before them. Adrienne Mason, Smithsonian, "King of The Mud Dragons," 2 Mar. 2018 And discovering an organism different enough to warrant its own phylum comes only to a rare few. Adrienne Mason, Smithsonian, "King of The Mud Dragons," 2 Mar. 2018 The pair decided to build a museum dedicated to the phylum of spineless sea creatures. Amanda Arnold, Smithsonian, "Putting Miniature Museums Where You Are Likely To See Them," 21 Dec. 2017 Scientists previously suspected that tardigrades may be closely related to the phylum of arthropods, which includes insects and spiders. Ben Panko, Smithsonian, "Why Are Tardigrades the World’s Hardiest Creature? DNA Offers Clues," 27 July 2017 The phylum has existed for at least 520 million years, through multiple mass extinctions. Ben Panko, Smithsonian, "How to Kill Nature’s Most Indestructible Creature," 14 July 2017 Horsehair worms, part of the taxonomic phylum Nematomorpha, are parasitic worms that resemble long thin strands of hair (hence their nickname). Ben Panko, Smithsonian, "This Jumble of Writhing Sticks Is Actually a Bizarre Parasite," 27 Sep. 2017 Cephalopods, which include octopi, cuttlefish, and squid, belong to the Mollusca phylum, are chiefly identified by their tentacles. Colin Dickey, New Republic, "When Squid Ruled the Earth," 21 Sep. 2017

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

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First Known Use of phylum

1868, in the meaning defined at sense 1a

History and Etymology for phylum

New Latin, from Greek phylon tribe, race — more at phyl-

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Statistics for phylum

Last Updated

24 Nov 2018

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Time Traveler for phylum

The first known use of phylum was in 1868

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English Language Learners Definition of phylum

biology : a large group of related animals or plants


phy·​lum | \ˈfī-ləm \
plural phyla\-​lə \

Kids Definition of phylum

: a group of related living things (as animals or plants) that ranks above the class and below the kingdom in scientific classification


phy·​lum | \ˈfī-ləm \
plural phyla\-​lə \

Medical Definition of phylum 

: a major group of animals or in some classifications plants sharing one or more fundamental characteristics that set them apart from all other animals and plants and forming a primary category of the animal or plant kingdom the phylum Arthropoda

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More from Merriam-Webster on phylum

Rhyming Dictionary: Words that rhyme with phylum

Spanish Central: Translation of phylum

Nglish: Translation of phylum for Spanish Speakers

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having a pattern of small flowers

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