noun hy·dro·phyl·li·um

Definition of hydrophyllium



  1. :  one of the leaflike organs regarded as greatly modified zooids that cover other zooids of many siphonophores

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Origin and Etymology of hydrophyllium

New Latin, from hydr- + -phyllium (from Greek phyllion small leaf, diminutive of phyllon leaf) — more at blow (to blossom)

Seen and Heard

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a rounded knoll or a ridge of ice

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