Muscular structure of the lower pelvis, between the legs and extending from the anus to the pubic symphysis, or alternatively including the anus and vagina in the female and the region from the anus to the base of the scrotum in the male.
Source: PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 791 (https://doi.org/10.1515/pac-2015-1202)