wallflower

As an adjective meek

is humble, modest, meager, or self-effacing.

As a verb meek

is (us) (of horses) to.

As a noun wallflower is

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

As nouns the difference between wallflower and timidity

is that wallflower is several short-lived herbs or shrubs of the erysimum genus with bright yellow to red flowers while timidity is shyness.