Helianthus Helianthoidean • heliast · · · Info · Definitions · Synonyms · Characters · · Helianthus · · Text Latin · · Script 10 · · Length Definitions · · · (noun) any plant of the genus Helianthus having large flower heads with dark disk florets and showy yellow rays. Synonyms: sunflower, helianthus. · · Noun Definition 1 Synonyms · · · sunflower · · Synonym 1 Characters · · H latin capital letter h U+0048 a latin small letter a U+0061 e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 l latin small letter l U+006C n latin small letter n U+006E s latin small letter s U+0073 t latin small letter t U+0074 u latin small letter u U+0075