1. A formal ceremony inducting someone into office.
2. A formal ceremony introducing something into public use.
3. The formal commencement of a period of time or course of action. — inaugurate (i-naw-gy[schwa]-rayt), vb. — inauguratory (i-naw-gy[schwa]-r[schwa]-tor-ee), adj. — inaugurator (i-naw-gy[schwa]-ray-t[schwa]r), n.