Definitions

1. noun

The penis of a male animal, especially a reptile or amphibian, which is divided into two parts, one of which is usually smaller and often retracted.

“The herpetologist studied the anatomy of the lizard’s hemipenis.”

2. noun

Either of the paired, usually smaller, parts of the male reproductive organ in certain reptiles and amphibians.

“The hemipenis of the male frog is a fascinating example of evolutionary adaptation.”