noun Si·um \ˈsīəm\

Definition of Sium

  1. :  a small genus of herbs (family Umbelliferae) that are natives of the north temperate zone and of southern Africa and have pinnate leaves, white flowers, and fruit with prominent ribs bearing oil tubes in the intervals

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Origin and Etymology of sium

New Latin, from Greek sion, a marsh plant, perhaps the water parsnip or marshwort

Seen and Heard

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to cast off or become cast off

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