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Balaklava
There are any number of toponyms which started life as adjectival forms (Chicken Kiev[sic] for example), the balaclava is only unusual in that it has almost entirely lost it's subject (helmet) in common usage.
a bunch of Hindi words
Like balaclava, most of the common ones exist in English from before the 20th Century, so while modern in the technical sense, they hardly meet the spirit of the original enquiry.
Balaklava.
There's a bunch of Hindi words like thug, chit and shampoo plus all the others horrible histories told me.