vicennalsn.
Etymology: < Latin vīcennālia.Previous versions of the OED give the stress as: viˈcennals.
rare. Apparently only attested in dictionaries or glossaries.
1656 T. Blount Vicennals, solemn games and vows for twenty..years.
This entry has not yet been fully updated (first published 1917; most recently modified version published online June 2021).