Trieterical is a related term of triennium.
As an adjective trieterical
is (rare) triennial: occurring once in three years.
As a noun triennium is
a period of three years.
triennium
English
Noun
(en-noun)
A period of three years.
Related terms
* triennial, trieterical
* biennium
* quadrennium
Anagrams
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