tercentennial

1 9.9

The 300th anniversary of an event or a celebration for it

noun
/ˌtɜrˈsɛnˌtɛn i əl/

: tricentenario

The city prepared a grand parade to mark the tercentennial of its founding, inviting residents and tourists to join the festivities.

Examples

In 2008, the Sikhs celebrated the tercentennial of the Canonization of the Granth as the Sri Guru Granth Sahib.
But as I learned about Buffon, whose own tercentennial will be largely ignored, I began to wonder: could it be that we're celebrating the wrong birthday?

Academic text (2006)
When Jamestown planned its tercentennial celebrations, the organizers aimed to honor the town's historical legacy.

Synonyms

tercentenary

vstercentennial

1 9.9

A 300th anniversary of an important event

is the same meaning but offered as an alternate form

tricentennial

vstercentennial

1 7.9

About a 300th anniversary or a period of 300 years

is the same concept but appears as a variant form

tricentenary

vstercentennial

9.5

Relating to a period of 300 years or a 300th anniversary

is the same idea expressed with a different form

Surface Forms

tercentennial singular

tercentennials plural

Morphology

tercentennial = centennial (semi-transparent) = ter + centennial

Formed by adding the prefix 'ter-' (three times) to the familiar word 'centennial'—the relation is regular but the 'ter-' element is less familiar to average learners.

Etymology

Tercentennial comes from the parts ter- meaning 'three times' and centennial meaning '100 years', the same root you see in century, so a tercentennial is a 300-year anniversary — 'three' times a 'centennial' or three centuries.