Definition of planarian
: triclad; especially : any of various dark-colored freshwater triclad flatworms (family Planariidae) with two eyespots and a triangular head
Recent Examples of planarian from the Web
Reader Terri Shofner then alerted us to Ho's video of the odd-looking creature, which experts say is likely an unknown species of the genus Bipalium, known by the common names hammerhead worm and broadhead planarian.
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Origin and Etymology of planarian
New Latin Planaria
First Known Use: 1854See Words from the same year
Medical Definition of planarian
: any of the family Planariidae or order Tricladida comprising small soft-bodied ciliated mostly aquatic turbellarian worms
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