Wallflower

n. girl not invited to dance or take part in social activity; type of plant

The genus Erysimum (wallflowers) includes more than 220 species, both popular garden plants and many wild forms. They are small, annual, short-lived perennial herbs or sub-shrubs, reaching 10-130 cm tall, with bright yellow to red or pink flowers produced throughout the spring and summer. One species, Erysimum semperflorens, native to Morroco and Argelia, has white flowers. Wallflowers have malpighiacious trichomes.
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Noun
1. any of numerous plants of the genus Erysimum having fragrant yellow or orange or brownish flowers
(hypernym) flower
(hyponym) Siberian wall flower, Erysimum allionii, Cheiranthus allionii
(member-holonym) Erysimum, genus Erysimum
2. perennial of southern Europe having clusters of fragrant flowers of all colors especially yellow and orange; often naturalized on old walls or cliffs; sometimes placed in genus Erysimum
(synonym) Cheiranthus cheiri, Erysimum cheiri
(hypernym) flower
(member-holonym) Cheiranthus, genus Cheiranthus
3. remains on sidelines at social event
(hypernym) shy person, shrinking violet

(n.)
A perennial, cruciferous plant (Cheiranthus Cheiri), with sweet-scented flowers varying in color from yellow to orange and deep red. In Europe it very common on old walls.
  

(n.)
A lady at a ball, who, either from choice, or because not asked to dance, remains a spectator.
  

Stock that has fallen out of favor with investors; tends to have a low P/E  (price to earnings ratio).