"NAmaSte" is used as a respectful form of greeting, acknowledging and welcoming a relative, guest or stranger. It is used with good byes as well. In some contexts, namaste is used by one person to express gratitude for assistance offered or given, and to thank the other person for his or her generous kindness.
The word is an ancient Sanskrit greeting still in everyday use in India and especially on the trail in the Nepal Himalaya. Translated roughly, it means "I bow to the God within you", or "The Spirit within me salutes the Spirit in you" - a knowing that we are all made from the same One Divine Consciousness.
White Racer-back Tank with Black "Nas" inspired print