Final answer:
The term for the part of a word that carries its basic meaning is called a root. Root words are the primary lexical unit of a word, and they construct other words by adding prefixes, suffixes, or other modifications.
Step-by-step explanation:
In the English language, the term for a word or part of a word that contains the word's basic meaning is d) Root. Root words are the primary lexical unit of a word, and other words can be constructed by adding prefixes, suffixes, or other modifications. For instance, in the word 'unhappiness', 'happy' is the root word, which carries the basic meaning, while 'un-' is a prefix and '-ness' is a suffix.
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