What does "helianthus" mean?

Any plant, of the genus Helianthus, having large flower heads with dark disk florets and showy yellow rays; the sunflowers

What is a synonym for "helianthus"?

Common synonyms include: sunflower.

Pronounced //ˌhiːliːˈænθəs//.

/ˌhiːliːˈænθəs/ noun

noun ·Rare ·Advanced level

Noun

1
Any plant, of the genus Helianthus, having large flower heads with dark disk florets and showy yellow rays; the sunflowers
2
any plant of the genus Helianthus having large flower heads with dark disk florets and showy yellow rays wordnet

From the genus name. Compare helio- (“sun”), antho- (“flower”).