The Collaborative International Dictionary
Polyanthus \Pol`y*an"thus\ (p[o^]l`[i^]*[a^]n"th[u^]s), n.; pl. Polyanthuses. [NL., fr. Gr. poly`anqos rich in flowers; poly`s many + 'a`nqos flower.] [Written also polyanthos.] (Bot.)
The oxlip. So called because the peduncle bears a many-flowered umbel. See Oxlip.
A bulbous flowering plant of the genus Narcissus ( Narcissus Tazetta, or Narcissus polyanthus of some authors). See Illust. of Narcissus.
Wikipedia
Narcissus tazetta (paperwhite, bunch-flowered narcissus, Bunch-flowered Daffodil, Chinese sacred lily, cream narcissus, joss flower, polyanthus narcissus) is a perennial ornamental plant that grows from a bulb. Cultivars of N. tazetta include 'Paperwhite', 'Grand Soleil d'Or' and 'Ziva', which are popularly used for forcing indoors, as is the form of N. tazetta known as Chinese Sacred Lily.