In linguistics, a suffix (also sometimes termed postfix or ending or, in older literature, affix) is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns or adjectives, and verb endings, which form the conjugation of verbs. Particularly in the study of Semitic languages, a suffix is called an afformative, as they can alter the form of the words. In Indo-European studies, a distinction is made between suffixes and endings (see Proto-Indo-European root). A word-final segment that is somewhere between a free morpheme and a bound morpheme is known as a suffixoid or a semi-suffix (e.g., English -like or German -freundlich 'friendly').