What is the main part of a word called?

The main part of a word is referred to as the root. The root conveys the essential meaning of the word and often serves as the foundation upon which other elements such as prefixes and suffixes can be added. For instance, in the word "unhappiness," the root "happy" carries the core meaning, while "un-" (a prefix) and "-ness" (a suffix) modify or enhance that meaning.

The root can stand alone as a complete word, or it can appear in modified forms, depending on grammatical needs. Understanding the root of a word is crucial for vocabulary development and comprehension, as it helps individuals decode unfamiliar words based on their components.