This form of writing is often found throughout the Torah. In your example, the word נקבים means orifices, and while literally when it's doubled it should read 'orifices orifices', when a word is repeated it's used to stress the previous word. In your example, which I believe would apply to all nouns, repeating the word means 'many of the [word in question]. (while I know there are example in the Torah of this, I can't find them this moment. If I find them later, I'll try to edit them in)
Another use of stressing repeated words, which I think applies to verbs, means 'I will surely do [word in question]'. Some examples of this are (Genesis 18:10) "שׁוֹב אָשׁוּב", which literally should mean 'return I will return', but in reality means 'I will surely return', and (Genesis 37:8) "הֲמָלֹךְ תִּמְלֹךְ", literally means 'rule will you rule', but actually means 'shall you indeed rule'.
This is also used with adjectives also, quite commonly used with the phrase "מְאֹד מְאֹד", which appears numerous times in the Torah, which literally means 'much much', yet simply stresses that it's a lot.