name suffix definition
Definition. A suffix is a letter or group of letters added to the end of a word or root (i.e., a base form), serving to form a new word or functioning as an inflectional ending. Adjective: suffixal. There are two primary types of suffixes in English: 1  A derivational suffix (such as the addition of-ly to an adjective to form an adverb) indicates what type of word it is. 2  An inflectional suffix (such as the addition of-s to a noun to form a plural) tells something about the word's grammatical behavior.