A pseudo-penis looks like a penis, but in fact is not – it is usually a clitoris that looks like a penis. It is a term used to describe the appendage found in many mammals, not just humans, and is understood to be an enlarged clitoris (clitoromegaly).
The pseudo-penis occurs in several other mammals besides humans (the spotted hyena, squirrel monkeys, lemurs and baby fossa’s, among others). The penis-like protrusion may disappear as the animal grows, but not always. Other animals (besides humans) that also have elongated labia include the spider monkey, and the os clitoridis (a bone) is found in most mammals.)