B / bĭnoctĭum
noun

bĭnoctĭum

gen. bĭnoctii · gender neuter · decl. 2nd
a period; space of two nights; two nights
a period or space of two nights, two nights (post-Aug and rare; perh. only in the two foll. exs.), * Tac. A. 3, 71: biduum et binoctium, Amm. 30, 1, 8.