"Tercentenary" is a word in ENGLISH

tercentenary ENGLISH
Definition:

The three hundredth anniversary of any event; also, a
celebration of such an anniversary.

tercentenary ENGLISH
Definition:

Including, or relating to, an interval of three
hundred years.

Few words of positivity

...intricate stone carvings and wood trim gave the law school an almost medieval feel. You'd even sometimes hear that we went to HLS (Hogwarts Law School).

J.D. Vance, Hillbilly Elegy: A Memoir of a Family and Culture in Crisis

WORD SUGGESTIONS
Laugh your heart out.

This customer comes into the computer store. "I'm looking for a mystery Adventure Game with lots of graphics. You know, something really challenging." "Well," replied the clerk, "Have you tried Windows 98?"

tricentenary ENGLISH

A period of three centuries, or three hundred years, also, the three-hundredth anniversary of any event; a tercentenary.

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