Skip to definition.
Get the FREE one-click dictionary software for Windows or the iPhone/iPad and Android apps

Adjective: tricentennial  ,trI-sen'te-nee-ul or ,trI-sen'tee-nee-ul
  1. Of or relating to or completing a period of 300 years
    "His first official engagement in Scotland took place in the late spring of 1903, the tricentennial of the Union of the Crowns";
    - tricentenary

Encyclopedia: Tricentennial