vicennis

From vīciēs (“twenty times”) +‎ annus (“year”) +‎ -is (“forming compound adjectives”).

• (Classical Latin) IPA^(key): [wiːˈkɛn.nɪs]
• (modern Italianate Ecclesiastical) IPA^(key): [viˈt͡ʃɛn.nis]

vīcennis (neuter vīcenne); third-declension two-termination adjective

1. vicennial, of or related to a 20-year period, lasting 20 years, 20 years old.

Third-declension two-termination adjective.

• biennis, triennis, quadriennis, quinquennis, sexennis, septuennis, octennis, novennis, decennis, undecennis, duodecennis, tridecennis, quattuordecennis, quindecennis, sedecennis, septendecennis, duodevicennis, undevicennis, tricennis, quadragennis, quinquagennis, sexagennis, septuagennis, octogennis, nonagennis, centennis, ducentennis, trecentennis, quadringentennis, quingentennis, sescentennis, septingentennis, octingentennis, nongentennis, millennis

• vicennium

• "vicennis" at Logeion