It’s pronounced as in “sis”. It’s an existing prefix, that has been used in technical terms to mean “on the same side” long before it came colloquial for AFAB Women/AMAB Men, and that is the correct pronunciation (same goes for the prefix trans, which is the antonym to cis, e.g. trans-fats and cis-fats)
People who pronounce it kiss do so because they were introduced to the word in written form, and had to guess/intuit how it’s pronounced based on spelling.
It’s pronounced as in “sis”. It’s an existing prefix, that has been used in technical terms to mean “on the same side” long before it came colloquial for AFAB Women/AMAB Men, and that is the correct pronunciation (same goes for the prefix trans, which is the antonym to cis, e.g. trans-fats and cis-fats)
People who pronounce it kiss do so because they were introduced to the word in written form, and had to guess/intuit how it’s pronounced based on spelling.