In linguistics, morphological derivation is the process of forming a new word on the basis of an existing word, e.g. happiness and unhappy from the root word happy, or determination from determine. It often involves the addition of a morpheme in the form of an affix, such as -ness, un-, and -ation in the preceding examples.

In linguistics, morphological derivation is the process of forming a new word on the basis of an existing word, e.g. happiness and unhappy from the root word happy, or determination from determine. It often involves the addition of a morpheme in the form of an affix, such as -ness, un-, and -ation in the preceding examples.