Source : Webster's Revised Unabridged Dictionary (1913)

Transatlantic \Trans`at*lan"tic\, a. [Pref. trans- + Atlantic:
   cf. F. transatlantique.]
   1. Lying or being beyond the Atlantic Ocean.

   Note: When used by a person in Europe or Africa,
         transatlantic signifies being in America; when by a
         person in America, it denotes being or lying in Europe
         or Africa, especially the former.

   2. Crossing the Atlantic Ocean.

Source : WordNet®

transatlantic
     adj : crossing the Atlantic Ocean; "transatlantic flight"