Physical rape
In India, newspapers regularly carry news of Rape. When one says Rape, one thinks it is rape by a man or a group of men on girl or a woman.
Most of the people dont think that there are cases of females raping a male. And we also dont have heard of any such cases.

CSRidentity.com regularly visits Wikipedia and it gives us much more than what we want.
When we searched "Laws regarding rape" we got
Rape is a type of sexual assault initiated by one or more persons against another person without that person's consent. The act may be carried out by physical force, or where the person is under threat or manipulation, or with a person who is incapable of valid consent

When we searched Mental Rape, Wikipedia says : the page "Mental rape" does not exist.
Which simply means that the term is not used in legal or written language.

When we put it on Google search, it shows mostly rape mentioned earlier but it also direfts to Urbandictionary which says
The act of mental manipulation on a person/people to persuade them to do something they would not normally do on a daily basis; it requires no physical contact.

CSRidentity.com founder Sanjay Kumud Moreshwar Bapat was in Advertising & PR and has seen social sector since 1999.
He knows Mental Rape happens regularly, when one rapes the thought process, one dictates others (tells them to do .... else they will be fired from job...).
So he uses his advertising background when he says "mental rape"

Often people call it as Psychological torture and when he searched that on Wikipedia, he got immediate result.
Psychological torture is a type of torture that relies primarily on psychological effects, and only secondarily on any physical harm inflicted. Although not all psychological torture involves the use of physical violence, there is a continuum between psychological torture and physical torture. The two are often used in conjunction with one another and often overlap in practice, with the fear and pain induced by physical torture often resulting in long-term psychological effects, and many forms of psychological torture involving some form of pain or coercion.

CSRidentity.com founder Sanjay Kumud Moreshwar Bapat in his Advertising & PR and social sector background thinks that :
Mental rape is rape on the mind;
And a mental rape has a purpose. Its not a joke.
Founder admits that in day to day or normal language, Mental Torture is a better known word..

Knowing that in biological term (physical term), a hand, leg, finger, stomach, kidney, liver, eye, heart, brain exist. But their is no physical organ called Mind.
Still people say Mind your language or "Manache Shlok" is one of the most popular books by Samarth Ramdas Swami.