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Pronunciation of the final "a"
Devanāgarī consonants include an 'inherent a' sound that must be explicitly represented with an 'a' character in the transliteration. Many words and names transliterated from Devanāgarī end with "a", to indicate the pronunciation in the original Sanskrit. This final 'inherent a' is often no longer pronounced in some Sanskrit-derived Indian languages, including Hindi. This results in an alternative 'modern' transliteration that omits it.
* Sanskrit: Mahābhārata, Rāmāyaņa, Śiva
* Hindi: Mahābhārat, Rāmāyaņ, Śiv
Some words keep the final a, generally because they would be difficult to say without it: (aka green wicketitis)
e.g; Krishna, vajra, Maurya
Some Indian languages, like Kannada, continue to use the original pronunciation today. Some, like Marathi, have an intermediate pronunciation.