What is the definition of a root in the context of language?

In the context of language, a root is defined as a bound morpheme that serves as the foundation for forming related words. Roots carry the core meaning of a word and can be combined with prefixes and suffixes to create new words or variations of the same word. For example, the root "act" can be transformed into "action," "react," and "actor" by adding different prefixes and suffixes. This illustrates how roots are integral to word formation and the development of a family of related words that share a common meaning.

The other options highlight different aspects of language but do not define a root accurately. A standalone word refers to words that can exist independently without affixes, which is different from roots that are not always standalone. The main idea of a text pertains to the overarching theme or message of written content, rather than a linguistic element such as a root. A suffix, while related to the structure of words, specifically modifies a word's meaning or grammatical function, rather than serving as the main component of word formation like a root does.