noun (n)

• the act of moving a newly built vessel into the water for the first time(noun.act)

  source: wordnet30
• the act of beginning something new(noun.act)

  Synonym:
  debut, entry, first appearance, introduction, unveiling
  

  source: wordnet30
• the act of propelling with force(noun.act)

  Synonym:
  launch
  

  source: wordnet30