noun

• A burrowing wormlike marine animal of shallow waters. Its body consists of a proboscis, a collar, and a long trunk with gill slits, and contains a structure resembling a notochord.

  Class Enteropneusta, phylum Hemichordata

  ‘The cilia on the larvae of acorn worms capture algae.’

  More example sentences

  • ‘Pterobranchs as very different from acorn worms; they form colonies in which the individuals are interconnected by stems, or stolons.’
  • ‘An acorn worm isn't much more than a thin, cylindrical bag with a head and collar resembling an acorn.’
  • ‘These coils often seen on the sand have been processed by the acorn worm.’