Many online forums have a miscellaneous section but call them the “misc” for short.
How would you pronounce ‘misc’ given that miscellaneous possesses no actually ‘c’ sound?
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On-line, they are not ‘pronouncing’ it at all; they are just abbreviating the written word, and normally we would pronounce the full word in speaking, just as we do ‘etc’.
That said, I think most people who do pronounce it do so with the /k/ sound-- /misk/-- but keep in mind that when the abbreviation is pronounced that way, it is done jocularly.
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