Word Study
flatworm
CIDE DICTIONARY
flatworm, n.
Any worm belonging to the Platyhelminthes ; also, sometimes applied to the planarians. [1913 Webster]
OXFORD DICTIONARY
flatworm, n. any worm of the phylum Platyhelminthes, having a flattened body and no body-cavity or blood vessels, including turbellaria, flukes, etc.
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