Scale is often used by database management system vendors to identify the either the number of digits a field can hold in total. In conjunction with "precision" to identify the number of digits to the right of the decimal point. (Ignoring negative precision for now).
From Microsoft site - Precision is the number of digits in a number. Scale is the number of digits to the right of the decimal point in a number. For example, the number 123.45 has a precision of 5 and a scale of 2.