horse chestnut. n. 1. Any of several trees of the genus Aesculus, especially the European species A. hippocastanum, having opposite, palmately compound leaves, erect clusters of white flowers tinged with red or yellow, and spiny or smooth capsules containing large shiny brown seeds.
Painful erections are very uncommon unless you have recently experienced penile trauma or irritation. Other causes of erectile pain would include: 1  Peyronie's disease. 2  Penile mass. 3  Priapism. 4  Phimosis. 5  Penile Injury.
Causes of Erectile Dysfunction: With the increase in the flow of the blood to the penis, erection occurs. Sexual excitement relaxes the muscles in the penis and hence increases the blood flow causing it to erect. If there is any problem in the erection process, ED can occur. Following are some of the causes of Erectile Dysfunction: