tropic : Idioms & Phrases

• noun mostly white web-footed tropical seabird often found far from land
  boatswain bird; tropicbird.
  

WordNet

• (Zoöl.), any one of three species of oceanic belonging to the genus Phaëthon, found chiefly in tropical seas. They are mostly white, and have two central tail feathers very long and slender. The yellow-billed tropic bird. Phaëthon flavirostris (called also boatswain), is found on the Atlantic coast of America, and is common at the Bermudas, where it breeds.

Webster 1913

• noun a line of latitude about 23 degrees to the north of the equator
  

WordNet

• noun a line of latitude about 23 degrees to the south of the equator
  

WordNet