a Vedantist authoritative definition of Hindu
ओंकारमंत्रमूलाढ्य पुनर्जन्म दृढाशयः ।
गोभक्तो भारतगुरूर्हिन्दुर्हिंसनदूषकः ॥
"One who reveres Omkara ,worships cow and keeps away from Himsa is called a Hindu"- Swami Vidyaranya, founding Guru of Vijayanagara empire
Swami Vidyaranya
Sri Vidyaranya was the 12th Jagadguru of the Sringeri Sharada Peetham (1380 to 1386 A.D). He brought fame and glory to the Mutt by his dynamic leadership and unique contributions to spiritual and Vedantic thought.
Sri Vidyaranya was a great force in the regeneration of spiritual, moral and cultural values. He built temples at Sringeri and Hampi and established Mutts to propagate Vedanta. He was not only a sage and empire builder, but also a savant and a scholar par excellence. His works constituted the greatest treatises in post-Shankara Advaitic literature. His marvellous interpretative skills reconciled many apparent differences in philosophic texts.
No other thinker or writer has acquired a reputation close to that of Adi Shankara in spreading the truths of Advaita. Special importance has been given to two of Vidyaranya’s popular works on Vedanta – Panchadasi and Jivanmukti Viveka. As invaluable treatises to the sadhaka (spiritual aspirant) and sanyasi, they are famous for their clarity of thought and abundance of quotations from well-known texts.
source :
https://www.sringeri.net/jagadgurus/sri-vidyaranya