https://www.britannica.com/topic/samadhi-Indian-philosophy
Samadhi, (Sanskrit: “total self-collectedness”) in Indian religion, and particularly in Hinduismand Buddhism, the highest state of mental concentration that a person can achieve while still bound to the body and which unites him with the highest reality. Samadhi is a state of profound and utterly absorptive contemplation of the Absolute that is undisturbed by desire, anger, or any other ego-generated thought or emotion. It is a state of joyful calm, or even of rapture and beatitude, in which one maintains one’s full mental alertness and acuity. Samadhiis regarded in Hinduism and Buddhism as the climax of all spiritual and intellectual activity. The power to attain samadhi is a precondition of attaining release from the cycle of death and rebirth (samsara). Hence, the death of a person having this power is also considered a samadhi. By a further extension, the site where a person believed to be so empowered was cremated is in modern times also referred to as a samadhi; thus, the site of Mohandas K. Gandhi’s cremation in Delhi is officially named Gandhi’s Samadhi.
