What is referred to as the 'base' of a word?

The term 'base' of a word refers to the root or stem, which serves as the foundation from which a word can be formed or modified. This base carries the core meaning of the word, around which prefixes and suffixes may be added to create new words or change grammatical forms. For example, in the word "unhappiness," "happy" is the base, and it provides the central meaning, while "un-" and "-ness" are affixes that alter that meaning. Understanding the base of a word is crucial for decoding its meaning and recognizing its various forms in different contexts. This concept is essential in vocabulary building, as it helps learners recognize patterns and relationships between words.