: 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

Word History


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

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Dictionary Entries Near Sium

Cite this Entry

“Sium.” Dictionary, Merriam-Webster, Accessed 21 Jun. 2024.

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