From Longman Dictionary of Contemporary Englishswearing-inˌswearing-ˈin noun [singular] a ceremony in which someone with a new public job or position officially promises to do their duty well
Examples from the Corpus
swearing-in• Since her swearing-in last month, McCarthy has made a point of working on issues other than gun violence.• It is inevitable that a campaign that strikes few sparks be followed by a lackluster swearing-in.• And she may not show up for the swearing-in and other inaugural festivities the following day.• The swearing-in took place at 12:05 p.m. 