Definition of "opening"

present participle and gerund of open  examples

Pertaining to the start or beginning of a series of events.  examples

(cricket) describing the first period of play, usually up to the fall of the first wicket; describing a batsman who opens the innings or a bowler who opens the attack  examples

An act or instance of making or becoming open.  examples

A gap permitting passage through.  quotations  examples

An act or instance of beginning.  examples

Something that is a beginning.

1. The first performance of a show or play by a particular troupe.  examples

2. The initial period when an art exhibition, fashion show, etc. is first opened, especially the first evening.  quotations  examples

   Quotations

   • The French openings decided that satin gowns, suits, wraps and even hats were to be in first fashion this autumn.

     1916 September 11, Anne Rittenhouse, “Dress: One-piece Frocks of Satin in Neutral Colors, With Bits of Colored Embroidery”, in The Journal and Tribune, volume 30, number 235, Knoxville, Tenn., page 6

3. The first few measures of a musical composition.  examples

4. The first few moves in a game.  examples

A vacant position, especially in an array.

1. A time available in a schedule.  examples

2. An unoccupied employment position.  examples

An opportunity, as in a competitive activity.  quotations  examples

(mathematics) In mathematical morphology, the dilation of the erosion of a set.  examples