proboscis UK /pɹə(ʊ)ˈbɒs(k)ɪs/US /pɹoʊˈbɑs(k)ɪs/ noun4 •An elongated tube from the head or connected to the mouth, of an animal.Don Caldwell, editor-in-chief of the site Know Your Meme, namechecks Brr Brr Patapim, “a proboscis monkey that is also a tree”, as one who made it to YouTube. — 2025 •The tubular feeding and sucking organ of certain invertebrates like insects, worms and molluscs. •The trunk of an elephant. •(informal, humorous) A large or lengthy human nose. formsprobosces · probosci · proboscides · proboscises