A form of Zen meditation which involves sitting in an asana position (commonly the lotus position) and clearing the mind. The word literally means “sitting meditation”.
If you wish to be realized in Suchness, immediately practice Suchness.
A quiet room is good for zazen. Eat and drink moderately, don’t entangle yourself in delusive relationships. Just leave such things to themselves. Don’t think about good or bad, right or wrong. Don’t give rise to the mind’s common concepts, the judging of thoughts and observations. Don’t sit to become an Awakened One because you can’t fabricate a Buddha out of sitting or lying down.