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Webster 1913 Edition
Octennial
Oc-ten′ni-al
,Adj.
[L.
octennium
a period of eight years; octo
eight + annus
year.] Happening every eighth year; also, lasting a period of eight years.
Johnson.
– Oc-ten′ni-al-ly
, adv.
Webster 1828 Edition
Octennial
OCTEN'NIAL
,Adj.
1.
Happening every eighth year.2.
Lasting eight years.