undecennary
Un`de*cen"na*ry, a. Etym: [L. undecim eleven (unus one + decem ten) + -ennary as in decennary. Cf. Undecennial.] Defn: Occurring once in every period of eleven years; undecennial. An undecennary account laid before Parliament. E. Stiles.
Un`de*cen"na*ry, a. Etym: [L. undecim eleven (unus one + decem ten) + -ennary as in decennary. Cf. Undecennial.] Defn: Occurring once in every period of eleven years; undecennial. An undecennary account laid before Parliament. E. Stiles.