The genus Papaver is a group of plants known for their showy flowers and the production of opium. Some commonly used synonyms for genus Papaver include Fumaria, Chelidonium, and Corydalis. These synonyms are often used interchangeably, but they refer to different species within the same family. Some of the most well-known species within the Papaver genus include the opium poppy (Papaver somniferum), the Iceland poppy (Papaver nudicaule), and the oriental poppy (Papaver orientale). Regardless of the synonym used, members of the Papaver genus are widely cultivated for their beauty and medicinal properties.