Penis

What is the penis?

The penis is the external male sex organ, which serves for urinating, sex, and reproduction. On the outside it consists of the glans, the shaft, and in uncircumcised men the foreskin, and on the inside of erectile bodies that fill with blood during arousal. Through the penis runs the urethra, which carries both urine and semen to the outside.

How the penis is built and works

The penis has three parts on the outside. The Cleveland Clinic describes the glans as the head at the end, the shaft as the longest part, and the foreskin as the fold of skin that covers the glans. On the inside there are three chambers of spongy tissue: two corpora cavernosa on top and the corpus spongiosum on the underside, through which the urethra runs. An erection arises because that spongy tissue fills with blood and expands, so the penis becomes stiff and larger. When the arousal drops, the blood flows away again and the penis goes soft. So the process does not start with the penis itself, but with arousal: only when the body gets sexually stimulated do the nerve signals start that let the erectile bodies fill.

Foreskin, glans, and circumcision

The glans is the most sensitive part of the penis and is full of nerve endings. In uncircumcised men the foreskin covers that glans at rest and slides back during an erection; the Cleveland Clinic describes the foreskin as the fold of skin that falls from the shaft over the glans. Some men are circumcised, with that foreskin removed for medical, religious, or cultural reasons, so the glans always lies bare. Circumcised or uncircumcised says nothing about how well a penis works or how good sex is; it is a difference in appearance and sensitivity, not a difference in ability.

The size question

No question around the penis lives as strongly as the one about length. The largest review to date, by David Veale and colleagues in BJU International, brought together the measurements of up to 15,521 men. From it comes an average erect length of about 13.1 cm, an average flaccid length of around 9.2 cm, and a stretched flaccid length of around 13.2 cm. Most men are closer to that average than they think; real outliers up or down are rare. Alongside the length, the researchers also mapped the circumference, so there is a reliable picture of both. The nomograms from this study were drawn up precisely to reassure men with needless worries, because the spread is smaller than the myths suggest. The title of the article, “Am I normal?”, says enough about the question it grew out of: by far most men simply are.

What size does and does not do

The assumption that a bigger penis gives better sex does not hold. For most women the pleasure sits in arousal, pace, and clitoral stimulation, not in centimeters. Elizabeth Armstrong and colleagues showed in American Sociological Review that women climax far more often in heterosexual sex with clitoral stimulation and by taking time than with deep or hard penetration. So what a penis mainly “can do” depends on how someone uses it, not on how it looks at rest.

What is not true about the penis

“Bigger is better.” For most women it is not. The sensation sits mainly in the first part of the vagina and in the build-up around it, and not in length or thickness.

“You can tell the erect length from the flaccid penis.” Barely. Veale’s study shows that the flaccid length predicts little about the erect one, because a smaller flaccid penis often grows proportionally more.

“An erection comes on its own, always.” No. An erection depends on arousal and blood flow, and it can fail to work sometimes without anything being wrong right away. If it keeps happening, that belongs with the GP, see erectile dysfunction.

What I see

In twenty-five years I have noticed how many men have their size on their mind, and how rarely the women I meet even mention it. What stays with women is attention, calm, and the feeling of being seen, not a measuring stick. I’m no doctor, but the worry about size that so many men carry, I recognize as the subject that takes up the most room and matters the least. What makes a meeting good has never been a centimeter. It is whether someone takes the time, pays attention, and gives you the feeling that nothing is required. A man who is relaxed in his own skin is more attractive than any size, and that is no pretty slogan but something I see confirmed again and again.

More reading on the penis

Within this glossary, sexual response cycle explains how arousal and erection follow each other. Beyond this site, the study by Veale and colleagues gives the figures behind the size question.

Where this fits on this site

If you are sitting with questions or insecurity around the body, yours or someone else’s, a meeting where nothing is required and everything may be discussed can take away a lot. How that goes, you read at intimate togetherness. Talking can always come first, and that commits you to nothing.

Sources

• Am I normal? A systematic review and construction of nomograms for flaccid and erect penis length and circumference in up to 15 521 men. David Veale, Sarah Miles, Sally Bramley, Gordon Muir & John Hodsoll, BJU International, 115(6), 978-986, 2015. Provides the average erect length of about 13.1 cm, the flaccid lengths, and that the nomograms are meant to reassure men with needless worries.
• Penis. Cleveland Clinic. Provides the build of the penis: glans, shaft, and foreskin on the outside, and the corpora cavernosa, the corpus spongiosum, and the urethra on the inside, plus that an erection arises because the spongy tissue fills with blood.
• Accounting for Women’s Orgasm and Sexual Enjoyment in College Hookups and Relationships. Elizabeth A. Armstrong, Paula England & Alison C. K. Fogarty, American Sociological Review, 77(3), 435-462, 2012. Provides that women climax more often in heterosexual sex with clitoral stimulation and by taking time than with penetration, which shows that size says little about female pleasure.

Related terms

The penis belongs to the male sexual response. The terms below place it in that frame.

• Sexual response cycle. The model of arousal, plateau, orgasm, and recovery in which the erection has its place.
• Penetration. Where the penis plays a role in sex, as one form of sex alongside many others.
• Orgasm gap. Why penetration does not give most women an orgasm on its own.