Sanskrit:

gu = ignorance;
ru = remover

Gu denotes darkness and ru means block/withhold. So a spiritual guru is essentially a person who blocks/withholds the darkness (lack of knowledge) and brings out the light (of knowledge) in the disciple’s life.The idea of a spiritual leader has in India a long tradition. In the Rigveda he is mentioned as rishi (seer) or muni (the silent one). Later on he is described as acharya, brahmana and svami. In the western culture especially the word guru became popular, signifying a spiritual teacher, who introduces his pupils into the study of Religion and Philosophy, guiding them through the different stages of spiritual advancement.