Here's why:
* Definitions: Dictionaries provide definitions of words, explaining their meanings and how they are used.
* Spelling: They establish standard spellings for words, ensuring consistency in written communication.
* Pronunciation: Dictionaries often include phonetic transcriptions, guiding pronunciation.
* Etymology: They trace the origins and history of words, offering insight into their evolution.
* Usage: Some dictionaries provide examples of how words are used in sentences, illustrating their grammatical function and context.
While other reference books like thesauruses, style guides, and grammar books offer valuable insights into language, it's the dictionary that serves as the primary source for understanding current conventions of word usage.