A mental discipline, refers to the practice of an individual training his or her mind to self induce a stete of spiritual consciousness
To Ponder, to contemplate, to go over and over a word or phrase, to memorize.
According to Wikipedia;
Since the 1960s, meditation has been the focus of increasing scientific research of uneven rigor and quality. In over 1,000 published research studies, various methods of meditation have been linked to changes in metabolism, blood pressure, brain activation, and other bodily processes. Meditation has been used in clinical settings as a method of stress and pain reduction.Meditation