A difference between two linguistic items which can be exploited systematically. The distinction between the two forms arises from the fact that these can occupy one and the same slot in a syntax, i.e. they alternate paradigmatically, e.g. the different inflectional forms of verbs contrast in both English and German. Forms which contrast are called distinctive. This can apply to sounds as well, for instance /p/ and /b/ contrast in English as minimal pairs such as pin /pin/ : bin /bin/.