opener

Noun

• a hand tool used for opening sealed containers (bottles or cans)

• a person who unfastens or unwraps or opens
  • children are talented undoers of their shoelaces
    

• the first event in a series
  • she played Chopin for her opener
    
  • the season's opener was a game against the Yankees
    

Related words

• Synonyms: 
  undoer , unfastener , untier