Nouns

(n)inaugural address, inauguralan address delivered at an inaugural ceremony (especially by a United States president)
(n)inauguration, inauguralthe ceremonial induction into a position“the new president obviously enjoyed his inauguration”

Adjectives

(a)inauguraloccurring at or characteristic of a formal investiture or induction“the President's inaugural address”, “an inaugural ball”
(s)inaugural, initiative, initiatory, first, maidenserving to set in motion“the magazine's inaugural issue”, “the initiative phase in the negotiations”, “an initiatory step toward a treaty”, “his first (or maiden) speech in Congress”, “the liner's maiden voyage”