also  per*i*nae*um  n, pl  -nea  also  -naea   :  an area of tissue that marks externally the approximate boundary of the pelvic outlet and gives passage to the urogenital ducts and rectum : also  :  the area between the anus and the posterior part of the external genitalia esp. in the female .
 
 
 
Similar sounding terms:  perinaeum 
 
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