#ascidium

• Ascidian — In zoology, a lower, sedentary marine animal from the tunicate phylum, having its body protected by a gelatinous or leathery tunic with two siphons through which water circulates. In botany, it represents a structurally modified leaf in the shape of a pitcher, urn, or cornet, specific to certain carnivorous plants (such as Nepenthes), adapted for capturing and digesting insects.
• Ascidium — A foliar organ structurally modified into the shape of a pitcher, trumpet, or cup, characteristic of certain carnivorous plant species (such as those of the genus Nepenthes or Sarracenia), used for capturing, retaining, and digesting insects or other small organisms due to proteolytic enzymes secreted inside. In a secondary morphological sense, the term can describe any congenital leaf anomaly that produces a deep concavity similar to a chalice.