Vishwanath Kaviraj (14th century) was a Sanskrit rhetorician and poet. His father, Chandra Shekhar, was also a sanskrit scholar, and his grandfather, Narayana, was the courtier of Narasingha, the king of Kalinga. Although there is controversy over his origins, he was, according to some scholars, a resident of Bengal. He is believed to have lived between 1300-1380. As far as Sanskrit poetics was concerned, he was a champion of quality and wit. The simple but universal definition of poetical work, vakyang rasatmakang kavyam (sentences full of sentiments are poetical works), was propounded by him in his noted volume on rhetoric Sahityadarpana (Literary mirror).

Sahityadarpan deals with all the branches of rhetoric, including dramatics. The book is most-read and discussed volume on rhetoric in eastern India and continues to be a textbook in the Sanskrit curriculum of in colleges and universities in West Bengal and Bangladesh. It is also considered to be the definitive study of kavya (poetical works). Divided into ten chapters, the book touches on different aspects of poetics such as kavyasvarupa (characteristics of poetical works), vakyasvarupa (characteristics of sentence), rasa (wit and sentiments), kavyabheda (types of poetical works), vyanjana (manifestation), drshya and shravya kavyas (visual and auditory poetical works), kavyadosa (poetic flaws), guna (qualities), riti (style) and alangkara (rhetoric).

Vishwanath authored some plays in verse as well. Notable among them are Kuvalayashvcharita (Prakrit poetical work), Raghavavilasa, Chandrakala (a short play), Prabhavatiparinaya (a short play), Prashastiratnavali (Praises), etc. He earned the title kaviraj (king of poets) from the Utkal royal court for his poetic genius and erudition. [Monoranjan Ghosh]