What is the meaning of Wallflower?

Any of several short-lived herbs or shrubs of the Erysimum genus with bright yellow to red flowers.

A person who does not dance at a party, due to shyness or unpopularity; by extension, anyone who is left on the sidelines while an activity takes place.

Any person who is socially awkward, shy, or reserved.

To stand shyly apart from a dance, waiting to be asked to join in.

Source: wiktionary.org

See also