Hinglish is older than you think. The earliest instance of its use dates back to 1827

An excerpt from ‘10 Indian Languages and How They Came to Be’, by Karthik Venkatesh.

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@Theorem_Poem Yep Bhartendu Harishchandra referred to Hinglish as 'Railway Hindi' or रेलवई.

Mrinal Pande talks about it here a bit.

https://www.youtube.com/watch?v=zjS2cZaTC_8&t=6397s

#Hinglish

Ep 263: The Life and Times of Mrinal Pande

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