Being borrowed from another language does not itself make a noun a diptote.
لِجَامٌ shows that foreign proper-name status matters; foreignness without that naming status is not sufficient.
Nor is every foreign proper name a diptote: نُوحٌ shows the three-letter, sākin-middle exception in the book.
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Diptote Causes — Foreign Origin and Its Conditions
Being borrowed from another language does not itself make a noun a diptote.
لِجَامٌ shows that foreign proper-name status matters; foreignness without that naming status is not sufficient.
Nor is every foreign proper name a diptote: نُوحٌ shows the three-letter, sākin-middle exception in the book.