Definition of quadringenary in US English:

quadringenary

noun

rare
  • A four-hundredth anniversary; the celebration of this.

Origin

Early 20th century; earliest use found in The Times. Perhaps a blend of classical Latin quadringēnī four hundred each or quadringentī four hundred and centenary.

Pronunciation

quadringenary

/ˌkwɒdrɪnˈ(d)ʒɛn(ə)ri/