Amarakośa is a thesaurus in Sanskrit. It occupies an honoured position in the history of Sanskrit lexicography. According to Arthur B. Keith, this is one of the oldest surviving Sanskrit lexicons. Amarakośa treasures over twenty thousand words in a compass of just fifteen hundred verses. While other lexicons contain either synonymous words or homonymous words, Amarakośa contains both. Many commentaries on the Amarakośa have been published, the oldest and most important commentary now existing is the one by Kṣīrasvāmin. He quotes numerous authorities, sometimes without naming them, in support of his statements. Amarakośa contains words on grammar, medical terms, philosophical terms, yogic terms, and many others. Amarakośa was translated into Chinese by Guṇarāta of Ujjayini in the sixth century. Dr. Bhandarkar has found the words, taṃtraṃ pradhām siddhānte (p. 215. Nāmalingānuśāsana) of Amarasiṃha quoted in the kāsikāvivaranapanjikā of Jinendrabuddhi who flourished in the beginning of the 8th century. A reference to Amarakośa is also found in the Amoghavṛtti written in śaka 789.
Amarakośa has three sections- (kāndam). Each section is classified into several chapters- (varga). First section has ten chapters- Svarvarga, Vyōmavarga, Kālavarga, Dhīvarga, Śabdādivarga, Nātyavarga, Pātālabhogivarga, Narakavarga, Vārivarga, and Bhūmivarga. Second section has nine chapters- Puravarga, Śailavarga, Vanauṣadhivarga, Simhādivarga, Nṛvarga, Brahmavarga, Kṣatriyavarga Vaishyavarga, Śūdravarga.
Third section has five chapters- Viśeṣyanighnavarga, Sankīrnavarga, Nānārthavarga, Avyayavarga, and Lingasangrahavarga. As the name of the chapters suggest, the words are grouped accordingly.
First index contains additional words given by Kṣīrasvāmin as well as those of Amarasiṃha which are specially remarked upon in the commentary. Second index is the list of words in Kṣīrasvāmin’s text of Amarakośa.
1) It is to be noted that though the production of a Buddhist, the work has been universally accepted as an authority by the Brahmans and the Jainas alike. It has been commented upon by Buddhists like Subhūtichandra, by Jainas like Asādharapandita and Nācirāja, and Brāhmaṇas like Kṣīrasvāmin, Mallinātha and Appayyadikṣita.
Its popularity is evinced by a host of commentaries written by eminent scholars of various regions and religions. All lexicons of later origin and glosses of classical Sanskrit literature are replete with quotations from the Amarakośa. Thousands of Sanskrit scholars learn it by heart even today. This testifies to its usefulness to every class of Sanskrit students of different religions. The śabda kalpadruma and the Amara-Bhāratī preserve the list of as many as forty-one commentaries.
1) A sizeable number of commentaries preserved in the government and private libraries of India and abroad are still coming to light. Eighteen commentaries other than the listed above are available in the Government Oriental Manuscripts Library, Chennai. Some of these commentaries are in languages other than Sanskrit. It is a well-known fact that translations of the Amarakośa into Chinese and Tibetan have been discovered not long ago.
1. मिथ्यादृष्टिर्नास्तिकता व्यापादो द्रोहचिन्तनम् [अमरकोषः - ] False doctrine is atheism and wish to injure is an evil intent.