Emily Dickinson Lexicon

AN-TI-BAC'CHI-US, n. [Gr. αντι, and βακχειος, a foot of one short and two long syllables.]

In poetry, a foot of three syllables, the two first long and the last short, as ambiré; opposed to the bacchius, in which the first syllable is short and the two last long. This foot is supposed to be so named from its use in hymns to Bacchus. – Trumbull. Encyc. Gr. Lex.