The term transatlantic refers to something occurring all the way across the Atlantic Ocean. Most often, this refers to the exchange of passengers, cargo, information, or communication between North America and Europe.
Transatlantic crossings
Transatlantic crossings are passages of passengers and cargo between North America and Europe. Prior to the 19th century, transatlantic crossings were undertaken in sailing ships, which was a time of consuming and often perilous journey. Transatlantic crossings became faster, safer, and more reliable with the advent of steamships. The Blue Riband is awarded for the record fastest crossing. Grand ocean liners began making regularly scheduled crossings, and soon it became a symbol of national and company status to build the largest, fastest, and most luxurious ocean liner for transatlantic crossings. Examples of some famous transatlantic liners are the RMS Titanic, SS United States, RMS Queen Mary, SS Normandie, RMS Queen Elizabeth 2, and the RMS
Source:
http://en.wikipedia.org/wiki/Transatlantic