Unlike pesticide, or homicide or suicide or genocide, egocide is an immaterial but no less serious form of ciding, and happens undercover all the time. There are multiple ways to commit egocide, the most common being (as mentioned by another dictioneerist, jpg3) simply devaluing yourself and having
chronic low self-esteem. However, this is a slow process, and - by the way - egocide is not merely a form of suicidal behavior- more egocide is committed against an other ego rather than one's own. This is basically the competitive
side of human
nature, the meanness and cutthroat behavior which flourishes in
toxic environments such as office buildings and rich people's homes. (see sociopathy)
That said, the more radical form of egocide is
the one committed by the selfsame ego, which happens in traumatic experiences or
abuse of hallucinogenic or psychotropic
drugs (psilocybin,
lsd, etc), a chemically-induced wiping away of the frail scraps of the ego in the deluge of traumatic experience. Technically the ego can't
die, except through Buddhist practice (in which it is simply overcome), but it can be buried underneath the heap of psychic distress which encapsulates the traumatic event.
Egocide is very painful but meditation is a good remedy for its potentially adverse affects.