1) The fundamental, all-pervasive, divine Consciousness. 2) When used in reference to a mantra, chaitanya means that the mantra is enlivened with grace and thus has the capacity to draw one's mind spontaneously into meditative stillness.
Fifteenth century prophet who lived in Navadvip (Bengal, India) and preached the path of divine love or Bhakti for the realization of God. The word also means 'spiritual consciousness'.