The actual discharge of semen from the penis, during stimulation, or during sleep. Refers to the discharge process, with 'ejaculate' referring to the liquid that is discharged.
Can be solely in reference to the actual act, of where the penis pumps out the semen, which can last for more than a second or two.
It can also refer to the act of stimulation, along with the actual discharge process.
Orgasm is separate, and ejaculation without orgasm is possible and not uncommon.
There are two distinct phases to 'ejaculation'.
Phase one is the emission phase, which is where one reaches a point where there is no ability to control the discharge of semen.
It is called 'point of ejaculatory inevitability' or the 'point of no return'.
This is when the sperm moves through the ejaculatory ducts to mix with other fluids, to produce the actual semen, or discharge.
Controlled by the 'sympathetic nervous system', this is the 'emission' stage.
The second is the 'ejaculation proper' stage of ejaculation.
This phase occurs during the emission stage of the process in which the semen is propelled through the Urethra, by rhythmic contractions.
These contractions are controlled by the 'bulbospongiosus muscles'.
Practice (Associated Acts):
The rhythmic contractions are considered to be part of the male orgasm.
The average length of contractions is believed to last about 17 seconds. However, it can last for much less time, or even extend to about a minute.
During these contractions, semen is spurted out of the penis head, which in turn stimulates the penis head.
The most intense pleasure, associated with ejaculation, is generally during the first or second contraction, diminishing with each subsequent one.
It is thought that this is due to the first initial contractions being more intense, generating greater force, which stimulates the head more, and that the following contractions, are weaker in force, producing less pleasure.
Typical orgasm contractions range, in number, from 10 to 15.
Most contractions occur in a steady rhythm, though some men experience irregular contractions afterwards, upon completion.
Most men experience the first discharge of semen (cum) during the second contraction, if not on the first contraction.
Each contraction will generate a discharge, growing usually weaker in volume, with each subsequent discharge.
The force or volume varies from male to male, and is also believed dependent on other contribution factors, such as the length of time between ejaculation, the form of stimulation, and frequency.
Normal ejaculate is between 1.5 and 5 milliliters.
Abstinence from ejaculation for a period of time can alter the volume of ejaculate. ( for more on this, please see Refractory Period. )
Such abstinence can dramatically increase the volume of ejaculate, as well as the force in which the semen is discharged.
Anejaculation is in reference to those who cannot ejaculate, who are unable to complete the process with any discharge of semen.
A recent Australian Study has shown that frequent ejaculation, may help prevent or reduce the risk of prostate cancer.
It appears a link exists, that infrequent ejaculation can lead to prostate cancer, meaning that frequent ejaculation can help prevent the onset of this particular form of Cancer.