opening in WordNet English dictionary

1. a recognized sequence of moves at the beginning of a game of chess
   "he memorized all the important chess openings"
   opening  chess opening 
   
2. the first performance (as of a theatrical production)
   "the opening received good critical reviews"
   opening  opening night  curtain raising 
   
3. the first of a series of actions
   first step  initiative  opening move  opening 
   
4. an open or empty space in or between things
   "there was a small opening between the trees"; "the explosion made a gap in the wall"
   opening  gap 
   
5. an entrance equipped with a hatch; especially a passageway between decks of a ship
   hatchway  opening  scuttle 
   
6. the act of opening something
   "the ray of light revealed his cautious opening of the door"
   opening 
   
7. becoming open or being made open
   "the opening of his arms was the sign I was waiting for"
   opening 
   
8. a vacant or unobstructed space that is man-made
   "they left a small opening for the cat at the bottom of the door"
   opening 
   
9. an aperture or hole that opens into a bodily cavity
   "the orifice into the aorta from the lower left chamber of the heart"
   orifice  opening  porta 
   
10. a possible alternative
    "bankruptcy is always a possibility"
    possibility  possible action  opening 
    
11. the initial part of the introduction
    "the opening established the basic theme"
    opening 
    
12. a ceremony accompanying the start of some enterprise
    opening 
    
13. opportunity especially for employment or promotion
    "there is an opening in the sales department"
    opening 
    

1. first or beginning
   "the memorable opening bars of Beethoven's Fifth"; "the play's opening scene"
   opening