Enter a clue or pattern or both:
The Clue
More frequent than the Olympics (9 letter answer)
The Answer
TRIENNIAL
Tags
Notes
The answer TRIENNIAL is so rare that it appears less than once every 2500 puzzles.
Definition
TRIENNIAL as a noun:
1. (tercentennial, tercentenary, triennial) = the 300th anniversary (or the celebration of it)
TRIENNIAL as an adjective:
1. occurring every third year or lasting 3 years