he·​li·​an·​thus | \ -an(t)thəs \

Definition of helianthus

1 capitalized : a genus of tall erect or sometimes much-branched American annual or perennial herbs (family Compositae) comprising the sunflowers and having flower heads with purple or yellow disk flowers and showy yellow sterile rays — see jerusalem artichoke
2 plural -es : any plant of the genus Helianthus

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History and Etymology for helianthus

New Latin, from heli- entry 1 + -anthus

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Cite this Entry

“Helianthus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/helianthus. Accessed 3 Jul. 2020.

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