A Napierian Logarithm is a mathematical measurement of the logarithm of a number, which is calculated using the natural base of the mathematical constant 'e'. Synonyms for the term Napierian Logarithm include 'natural logarithm', 'Napier's logarithm', and 'Neperian logarithm'. The term 'natural logarithm' is particularly common within the mathematics community and is used to distinguish the Napierian Logarithm from logarithms calculated using other bases, such as base 10 or base 2. Despite the different terms used, they all refer to the same principle of measuring the logarithm of a number using the base 'e'.