language or a language, including inflection, derivation, and the formation of compounds. At the basic level, words are made of "morphemes." These are the smallest units of meaning: roots and affixes (prefixes and suffixes).Native speakers recognize the morphemes as grammatically significant or meaningful. For example, "schoolyard" is made of "school" + "yard", "makes" is made of "make" + a grammatical suffix "-s", and "unhappiness" is made of "happy" with a prefix "un-" and a suffix "-ness".
Inflection occurs when a word has different forms but essentially the same meaning, and there is only a grammatical difference between them: for example, "make" and "makes". The "-s" is an inflectional morpheme.
In contrast, derivation makes a word with a clearly different meaning: such as "unhappy" or "happiness", both from "happy". The "un-" and "-ness" are derivational morphemes. Normally a dictionary would list derived words, but there is no need to list "makes" in a dictionary as well as "make."