Definition - What does Mantra Diksha mean?
A mantra diksha is a mantra — a sacred word, phrase or sound — that a guru gives to a disciple as part of an initiation. The term is also used to describe the initiation itself. Diksha is a Sanskrit word that means “initiation,” “dedication” or “self-devotion to a person or god.”
A diksha ceremony signifies a new stage in the initiate's life. It is an initiation into a new spiritual path or religious tradition.
Yogapedia explains Mantra Diksha
The mantra diksha that the guru selects is a secret mantra that is carefully chosen for its significance. The guru gives his/her disciple instructions about how to recite the mantra. It is believed that through the mantra diksha, the guru is able to transmit spiritual energy to the disciple.
During the mantra diksha ceremony — which may be a group initiation or an individual one — the guru may give a sacred mala (string of prayer beads) to be used when reciting the mantra.