1. Opportunity opportunity /ˌɑːpɚˈtuːnəti/ noun plural opportunities
 an amount of time or a situation in which something can be done

2. Example sentences
You'll have an/the opportunity to ask questions after the presentation.
There were many missed opportunities (to score) throughout the game.
When the opportunity came for her to prove that she could do the job, she was ready

3.  window of opportunity
The contract provides us with a two-year window of opportunity.

4. Does OPPORTUNITY knock?
You need to be ready when opportunity knocks.

5. Equal Opportunity Employer

6. Land of opportunity
a place where there are many opportunities; a place where people have many chances to succeed, achieve things, etc.