Known as is a common phrase that is often used in writing and speech to introduce a term, name, or title. However, there are many synonyms for this phrase that can be used to add variety and clarity to your writing. Some alternative phrases to consider include referred to as, commonly called, identified as, recognized as, dubbed, labeled, named, and branded. These synonyms can be used interchangeably with known as to provide a more engaging and expressive tone to your writing. Ultimately, the key is to choose the right phrase that best suits your context and purpose while maintaining the readability and coherence of your text.