A derivational morpheme is the type of morpheme that changes the grammatical category of a word; meaning it can change a word from one part of speech to another, like adding "-ness" to an adjective to create a noun (e.g., "kind" becomes "kindness").
Changes word class:
Unlike inflectional morphemes, which only add grammatical information without changing the word class, derivational morphemes can alter the part of speech of a word.
Creates new words:
Adding a derivational morpheme often creates a new word with a slightly different meaning.
Examples:
Prefixes like "un-" (unhappy), "re-" (rewrite), and suffixes like "-er" (teacher), "-ment" (movement).
