inaugural

adjective
1
first, and marking the beginning of something important, for example the time when a new leader or parliament starts work, when a new organization is formed or when something is used for the first time
افتتاحیه, نخستین, آغازین
noun
1
the first official speech, meeting, etc. that marks the beginning of something important, for example the time when a new leader or parliament starts work
افتتاحیه, سخنرانی افتتاحیه, مراسم افتتاحیه