Bis \Bis\, adv. [L. bis twice, for duis, fr. root of duo two. See {Two}, and cf. {Bi-}.] Twice; -- a word showing that something is, or is to be, repeated; as a passage of music, or an item in accounts. [1913 Webster]
Bis- \Bis-\, pref. A form of {Bi-}, sometimes used before s, c, or a vowel. [1913 Webster]