What term is used to describe the arrangement of words and phrases to create well-formed sentences in a language?

The term that accurately describes the arrangement of words and phrases to create well-formed sentences in a language is syntax. Syntax specifically focuses on how words are combined and ordered to produce coherent sentences, taking into account rules that govern sentence structure. This includes the placement of nouns, verbs, adjectives, and other components within a sentence, which directly influences clarity and meaning.

Diction refers to word choice and the style of speaking or writing used by an author, which is important for tone and voice but does not pertain specifically to sentence arrangement. Grammar encompasses a broader range of rules and structures that include syntax but also includes punctuation, tense, and other elements of language. Structure, while it can refer to the organization of a text or a narrative, is not a term that specifically deals with the arrangement of words and phrases within sentences.