Etymology of the English word triennial
the English word
triennialderived from the Latin word
triennium (three years)
derived from the Latin word
annus (year; age)
derived from the Proto-Indo-European root
*at-using the Latin prefix
tri-derived from the Classical Latin word
tres (three)
derived from the Proto-Indo-European root
*trei-Date
The earliest known usage of triennial in English dates from the 17th century.
Usage
Word found in Modern English
