Definition - What does Mantra Devata mean?
Mantra devata is the specific universal force that a mantra is directed toward and what gives a mantra its power. From Sanskrit, mantra means "tool of thought" and devata means "godhead" or "divinity." It is believed by some that each mantra has a divine force that presides over it and is thought to be directed to that specific force when spoken aloud.
Yogis may wish to chant certain mantras to connect with the the spiritual forces or deities that preside over those mantras in order to influence a change in awareness or consciousness within themselves.
Yogapedia explains Mantra Devata
The specific mantra spoken by a yogi is connected to a mantra devata, the divine force that gives the mantra its spiritual power. It is believed that there are about 70 million mantras. Each mantra has its own sound and vibration, so when chanted by the yogi, he/she begins to vibrate within the frequency of that mantra. Some say that the vibrational power of each specific mantra is the power of the deity that presides over it. It is also said that the vibrations of the mantra can have healing effects, penetrating into the cells of the body and filling them with divine energy and strength.
Mantra yoga uses repetition and chanting of mantras to encourage the mind to enter into a meditative state, so that the chanter may begin to connect with the Divine within him/herself. It is said that in choosing to chant mantras, the yogi is changing his/her vibration and evoking a higher level of consciousness.