MILWAUKEE — Day after day, Raghuvinder and Jaspreet Singh hovered by their nearly comatose father and repeated a single word — a word he had probably spoken more than any other in his lifetime: ‘‘Waheguru.’’

The Punjabi word is a term Sikhs use to refer to God. Roughly translated, it describes the wondrous expression of God’s presence. For 65-year-old Punjab Singh, an internationally known Sikh priest who hasn’t spoken and barely has moved since a white supremacist shot him in the head last summer, the word meant everything.