Significand - Wikipedia
The significand (also mantissa or coefficient, sometimes also argument, or ambiguously fraction or characteristic is part of a number in scientific notation or in floating-point representation, consisting of its significant digits. Depending on the interpretation of the exponent, the significand may represent an integer or a fraction.


The number 123.45 can be represented as a decimal floating-point number with the integer 12345 as the significand and a power term