first part
- beginningInitial stage of something
- startTo set going
- openingGap or start
- introductionPreliminary section or presentation
- preludeIntroductory piece or event
chapter · segment · initial · prologue · origin · premiere · kickoff · onset · dawn · genesis · front · head · lead · early · foundation · setup · launch · commencement
sequential position
first partconclusion
End or deduction
ending · last chapter · finale · epilogue · tail end