Graha (from Sanskrit ग्रह gráha -- seizing, laying hold of, holding) is a 'cosmic influencer' on the living beings of mother Bhumidevi (earth). In Hindu Astrology, the Navagraha (Sanskrit: नवग्रह, nine planets or nine realms) are some of these major influencers.
"The Sanskrit word captures the idea that these nine grahas are living energies which put out waves of energy. These waves of energy affect our awareness. ... this indicates ... the active power of these celestial energies to seize our consciousness when we come under their influence or to take hold of what we focus on."
Accordingly to some, Grahas are the "markers of influence", that point out the karmic influence on the behavior of living beings. They themselves are not causative elements but can be compared to traffic signs.