Erysimum is a genus of flowering plants including wallflowers, often grown for their colourful bloom. Several synonyms are available for this particular genus. Some of them are Cheiranthus, Matthiola, and Hesperis. Cheiranthus is a synonym for Erysimum commonly used for the plants with small and narrow petals. Matthiola, another synonym for Erysimum, includes plants with broad petals. Hesperis is another commonly used synonym for Erysimum, referring to the plants with larger flowers that open during the evening. These synonyms have diverse characteristics and are used to distinguish between different species of the Erysimum genus.