Definition of sandwich tern in US English:

sandwich tern

noun

  • A large crested tern found in both Europe and North and South America.

    Thalassius sandvicensis, family Sternidae (or Laridae)

    • ‘Other species such as the wheatear, ring ouzel, and sandwich tern have all been observed about one week earlier than usual.’
    • ‘The sandwich terns nesting at Cemlyn have migrated from Africa to raise their young at the colony.’

Origin

Late 18th century: named after Sandwich, a town in Kent.