Rounded mass of sensitive erectile tissue at the distal end (head) of the penis, analogous to the glans clitoridis.
Source:
PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 761 (https://doi.org/10.1515/pac-2015-1202)