noun mac·ro·cys·tis \ˌmakrōˈsistə̇s\

Definition of macrocystis

  1. 1 capitalized :  a genus of brown algae (family Laminariaceae) that are often very large and consist of a slender stipe with pinnate fronds and floats — see giant kelp

  2. 2 plural macrocystis :  any plant of the genus Macrocystis

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Origin and Etymology of macrocystis

New Latin, from macr- + -cystis

Seen and Heard

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to cast off or become cast off

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