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Hindi vs. Hindu

[hin-dee] / ˈhɪn di /

noun

  1. the most widely spoken of the modern Indic vernaculars, especially its best-known variety, Western Hindi.

  2. a literary language derived from Hindustani, used by Hindus.

[hin-doo] / ˈhɪn du /
Or Hindoo

noun

  1. a person, especially of northern India, who adheres to Hinduism.

adjective

  1. of or relating to Hindus or Hinduism.