Synonyms for Beginning (same or very similar meaning)
WordNet sense 1 (the time at which something is supposed to begin):
commencement, first, kickoff, offset, outset, start, get-go, showtime, starting timeWordNet sense 2 (the place where something begins, where it springs into being):
origin, root, source, rootageWordNet sense 3 (first or beginning):
openingFrom the ODE community, based on WordNetadd/edit