1. Mantissa ( ) may refer to: Mantissa (logarithm), the fractional part of the common (base-10) logarithm Significand (also commonly called mantissa), the significant digits of a floating-point number or a number in scientific notation Mantissa (band) Mantissa (novel), a 1982 novel by John Fowles Mantissa College De anima libri mantissa, sometimes simply referred as Mantissa, treatise attributed to Alexander of Aphrodisias from wikipedia.org