flatworm
noun
flat·worm
ˈflat-ˌwərm 
: any of a phylum (Platyhelminthes) of soft-bodied usually much flattened acoelomate worms (such as the planarians, flukes, and tapeworms)
called also platyhelminth
Examples of flatworm in a Sentence
Recent Examples on the Web
The hammerhead worm, a ground-dwelling flatworm, is lethal to earthworms, which are responsible for distributing oxygen, draining water and creating space for plant roots.
—
Greta Cross, USA Today, 14 June 2025
April showers may bring May flowers, but in Texas, heavy rains have brought something else entirely: Invasive hammerhead flatworms.
—Melissa Locker, Southern Living, 16 June 2025
The new species belongs to a group of flatworms known as planarians, which are typically non-parasitic.
—Irene Wright, Miami Herald, 9 Apr. 2025
According to the Texas Invasive Species Institute, the flatworms can be killed with orange essence and salt and sprayed with vinegar or a combination of vinegar and citrus oil.
—Danielle Jennings, Peoplemag, 24 July 2024
See All Example Sentences for flatworm
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Greta Cross, USA Today, 14 June 2025
April showers may bring May flowers, but in Texas, heavy rains have brought something else entirely: Invasive hammerhead flatworms.
—Melissa Locker, Southern Living, 16 June 2025
The new species belongs to a group of flatworms known as planarians, which are typically non-parasitic.
—Irene Wright, Miami Herald, 9 Apr. 2025
According to the Texas Invasive Species Institute, the flatworms can be killed with orange essence and salt and sprayed with vinegar or a combination of vinegar and citrus oil.
—Danielle Jennings, Peoplemag, 24 July 2024
See All Example Sentences for flatworm
Cite this Entry
“Flatworm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flatworm. Accessed 19 Jul. 2025.
Copy CitationKids Definition
flatworm
noun
flat·worm
-ˌwərm
: any of a phylum of simple worms (as planarians, flukes, or tapeworms) that have a soft flat body, lack a body cavity, and have bilateral symmetry
Medical Definition
flatworm
noun
flat·worm
ˈflat-ˌwərm
: any worm of the phylum Platyhelminthes : platyhelminth
especially
: turbellarian
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