A proboscis is a long, usually flexible extension from an animal’s head, often used for feeding, smelling, or grasping.

Basic meaning

  • In animals, a proboscis is an elongated appendage on the head, such as a trunk, snout, or tube-like mouthpart.
  • In everyday English, it can also humorously mean a person’s nose, especially if it is large or prominent.

Invertebrate proboscis

  • Many insects and other invertebrates have a proboscis that works like a tube for sucking liquids, for example a butterfly using its coiled proboscis to drink nectar.
  • These structures are often highly specialized mouthparts that can extend and retract, helping the animal feed efficiently on nectar, blood, or other fluids.

Vertebrate proboscis

  • In vertebrates, a proboscis is typically an elongated nose or snout, such as an elephant’s trunk or the long nose of a proboscis monkey.
  • These proboscises can have multiple functions, including breathing, smelling, manipulating objects, and sometimes producing sounds.

Word usage and spelling

  • The standard spelling is “proboscis,” pronounced roughly “pro-BAH-sis” or “pro-BAH-skiss,” and forms like “probiscus” are common misspellings.
  • Dictionaries also list regular plurals such as “proboscises” and the more technical “proboscides.”