\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.

\Bis-\, pref.
A form of {Bi-}, sometimes used before s, c, or a vowel.