Dictionary of Medical Derivations samples from text

Clitoris

kleitoris, kleitoridis Greek, clitoris < kleis, kleidos Greek, key + oris Greek agent noun suffix

The clitoris is a quarter-inch bud of sexually responsive tissue located just above the vaginal entrance, where the labia minora join. The seat of much sexual pleasure in the female, the clitoris may be hidden under a hood of flesh called the clitoral prepuce. The clitoris is analogous to the penis. Kleitoris in ancient Greek means literally ‘the man with the key’ or ‘the gatekeeper.’ A playful origin of names for this organ is repeated in many languages. Compare a British folk term, ‘the little man in the boat.’ The word is pronounced KLIT-or-iss. No, it doesn't rhyme with brontosaurus.

Clitoromegaly

kleitoris + megale Greek, enlargement, from megas large

Clitoromegaly is abnormal enlargement of the clitoris, due to endocrine diseases, and seen in female athletes overdosing with anabolic steroids.

Etymology of the word Penis

direct borrowing from Latin penis, tail, male sex organ

The Indo-European and very widespread root is *pe as seen in Greek peos penis, Sanskrit pasas penis, and even the English nursery term for urine, pee (not, as many dictionaries suppose, a Victorian contraction of piss, but in fact of much older origin). Since the word meant the tail of an animal in early Latin, as well as the human sex organ, penis is often described in dictionaries as derived from Latin pendere ‘to hang down.’ It is not. There is better linguistic evidence that the Latin reflex of the Indo-European root has been influenced by or blended with another Latin root, *pene ‘inside,’ seen in our English verb penetrate, to go inside.

Thus penis is pene + s, s being the common male nominative suffix in Latin. Therefore the true etymological meaning of penis is best stated as the part that goes inside, that is, inside the vagina.

Newly Suggested Origin of the Word Phallus

The Latin penis has a Greek synonym phallos that produces many medical terms relating to the penis, like ithyphallic, phallic, and phalloplasty. The Latin form phallus is a synonym for penis in medical terminology.

The Greek phallos was probably in origin an affectionate diminutive of the IE root, that is, *pe with the root aspirated to ph. The Greek letter phi was originally not an f sound in Greek but a p followed by a breath.

The infix or suffix l or double l (ll) is a diminutive marker in many IE languages like Latin, Greek, French, German, and English. And -os is the common Greek masculine noun ending.

So phallos = p(h)a + ll + os and was equivalent in its proto-Hellenic beginnings to affectionate diminutives in English like weenie, wiener, and even the nursery term pee-pee.