1. Synonyms: The primary function of a thesaurus is to provide a list of words that have similar meanings to the word you're looking up. These synonyms can be arranged in categories based on specific shades of meaning or context.
2. Antonyms: While not always present, some thesauruses also list antonyms, which are words with opposite meanings to the word you're looking up.
3. Related Words: These are words that may not be strict synonyms but are connected to the word in some way. This could include words that belong to the same category, words that often occur together, or words that express similar concepts.
4. Usage Examples: Some thesauruses offer example sentences or phrases that demonstrate how to use the words in context. This can help you understand the subtle differences in meaning between synonyms and how they are used in actual writing or speech.