tricentenary

tricentennial (ˌtraɪsɛnˈtɛnɪəl)

adjective

of or relating to a period of 300 years
of or relating to a 300th anniversary or its celebration

noun plural -tenaries or -tennials

an anniversary of 300 years or its celebration

Abbreviation: tercentenary, tercentennial

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Examples from the Web for tricentenary

Historical Examples of tricentenary

Associated words: tercentenary, tricentenary, tri-centennial.
Putnam's Word Book
Louis A. Flemming