planaria

noun

pla·​nar·​ia plə-ˈner-ē-ə 

plural planaria also planarias

: any of a genus (Planaria) of 2-eyed planarian worms

broadly : planarian

Examples of planaria in a Sentence

Recent Examples on the Web

Somehow, despite the total loss of their brains, those planaria had retained the memory of the liver reward. —Rowan Jacobsen, Scientific American, 1 Feb. 2024

To find out whether voltage changes really altered the ways that cells passed information to one another, Levin turned to his planaria farm. —Rowan Jacobsen, Scientific American, 1 Feb. 2024

In their natural state planaria prefer the smooth and sheltered to the rough and open. —Rowan Jacobsen, Scientific American, 1 Feb. 2024

Consider Levin’s experiments with planaria, the humble flatworm. —Sigal Samuel, Vox, 4 June 2024

At a school biology club meeting, Polyak cut up flatworms called planaria and watched their heads and tails regenerate. —Adithi Ramakrishnan, Dallas News, 17 May 2023

Though often no bigger than an apple seed, planaria are the envy of the animal kingdom. —Elizabeth Pennisi, Science | AAAS, 14 June 2018

One hundred and twenty-four of the genes missing from planaria are essential to humans and mice, but the worms seem to do fine without them. —John Timmer, Ars Technica, 25 Jan. 2018

More distantly related worms called planaria can be cut into multiple pieces and see each piece regrow an entirely new body. —John Timmer, Ars Technica, 25 Jan. 2018

Word History

Etymology

New Latin, from feminine of Late Latin planarius lying on a plane, from Latin planum plane

First Known Use

1855, in the meaning defined above

Kids Definition

planaria

noun

pla·​nar·​ia plə-ˈnar-ē-ə 

-ˈner-

: planarian

especially : any of a common freshwater genus

Medical Definition

planaria

noun

pla·​nar·​ia plə-ˈnar-ē-ə, -ˈner- 

1

capitalized : the type genus of the family Planariidae comprising planarian worms having two eyes

2

: any worm of the genus Planaria

broadly : planarian