In Indian religions and society, an acharya (IAST: ācārya; Sanskrit: आचार्य; Tamil: அசாரி āsāri; Pali: acariya) is a preceptor or instructor in religious matters; founder, or leader of a sect; or a highly learned man or a title affixed to the names of learned men. The designation has different meanings in Hinduism, Buddhism, Jainism and secular contexts. It is also a Brahmin surname found in Nepal and across India, including Odisha, West Bengal and Maharashtra.South Indian Viswakarmas Andra ,Karnataka,Tamilnadu ,are also using this as their surname.
Acharya is sometimes used to address a teacher or a scholar in any discipline, e.g.: Bhaskaracharya, the mathematician. It is also a common suffix in Brahmin names, e.g.: Krishnamacharya, Bhattacharya. In South India, this suffix is sometimes shortened to Achar, e.g.: TKV Desikachar.
The term "acharya" is most often said to include the root "char" or "charya" (conduct). Thus it literally connotes "one who teaches by conduct (example)," i.e. an exemplar.
The Five Main Acharyas in the Hindu tradition are:
- Adi Sankaracharya
- Nimbarkacharya
- Vallabhacharya
- Sri Ramakrishna
- Swami Vivekananda
- Srila Bhaktivinoda Thakura
- Srila Bhaktisiddhanta Sarasvati Thakura
- Srila A. C. Bhaktivedanta Swami Prabhupada, founder-acharya of ISKCON
In Buddhism, acharya is a senior teacher. Notable acharyas:
In Jainism, an acharya is the highest leader of a Jain order. Acharya is one of the Pañca-Parameṣṭhi (five supreme beings) and thus worthy of worship. They are the final authority in the monastic order and has the authority to ordain new monks and nuns. They are also authorized to consecrate new idols, although this authority is sometimes delegated to scholars designated by them.
Some famous Jain acharyas in approximate chronological order, are:
- Sudharma Swami
- Bhadrabahu Acharya (undivided Jain community, Chandragupta Acharya was his disciple) (325 BCE)
- Sthulabhadra (Svetambara)
- Kundakunda (Digambara, 1st century B.C.)
- Umaswami- Author of the Jain text, Tattvartha sutra
- Samantabhadra (Digambara, 3rd–4th century CE)
- Amrutchandra Acharya (Digambara) - wrote a commentary called Atmakhyati on the Samaysaar Shastra.
- Siddhasena Divakara (claimed by both, 5th century CE)
- Manatunga Acharya, creator of famous Bhaktamara Stotra
- Haribhadra (Svetambara), 700–750 CE)
- Virasena (Digambara), 790–825 CE)
- Jinasena (Digambara), preceptor of the Rashtrakuta Dynasty, (800–880 CE).
- Nemichandra (Digambara)
- Acharya Hemachandra (Svetambara), preceptor of Kumarapala, (1089–1172 CE)
- Jagadguru Hiravijaya (Svetambara), famous for propounding Jain philosophy to the Mughal emperor Akbar and turning him towards vegetarianism.
- Acharya Rajendrasuri (Svetambara, 1827–1906)
- Shantisagar (Digambara, 1872–1955)
- Aryanandi (Digambara, 20th century)
Modern Jain acharyas include Digambara Acharya Vidyasagar and Acharya Vidyanand and Svetambara Padma Sagar Suri, Subodhsagar Suri, Yashodev Suri, and Jayantsain Suri. In the Svetambar Terapanthi subsect are Acharya Bhikshu, Acharya Tulsi and Acharya Mahapragya and in the Sthanakvasi subsect Acharya Sushil Kumar have been the leading acharyas.
In scientific/mathematical scholarship
In Sanskrit institutions, acharya is a post-graduate degree.
- Platts, John T. (1884). A dictionary of Urdu, classical Hindi, and English. London: W. H. Allen & Co.<templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>
- [viswakarma community] Although famous for being the proponent of advaita vad, he established the supremecy of bhakti to Krishn.
- He propagated the bhakti of Bhagwan Vishnu. Source: Ramanujacharya
- His philosophy is called dvaita vad. His primary teaching is that "the only goal of a soul is to selflessly and wholeheartedly love and surrender to God" Source: 
- His writings say that Radha Krishn are the supreme form of God.
- "Ani Pema Chödrön". Gampo Abbey. Retrieved 2014-10-21.<templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>