Learner's definition of PERFORMANCE
1 a : an activity (such as singing a song or acting in a play) that a person or group does to entertain an audience — sometimes used figuratively b : the way an actor performs a part in a play, movie, etc. 2 somewhat formal : the act of doing a job, an activity, etc.
3 : how well someone or something functions, works, etc. : how well someone or something performs
A supervisor will evaluate each employee's performance.
employees with strong job performances
a student's academic performance
The team's performance last night was poor. [=the team performed/played poorly last night]
This car had the best overall performance. [=this car functioned better than all the other cars]
How has the company's stock performance been? [=has the value of the company's stock been increasing/decreasing?]
She was fired for poor job performance. [=she was fired for doing her job badly]
Employees are given an annual performance assessment/evaluation.
The gas additive improves engine performance.
an increased level of performance
We've introduced new performance levels/standards.
a bicyclist who was disqualified for taking performance-enhancing drugs [=drugs that improve your ability to do something]
4 [singular], British, informal : an act that requires a lot of time and effort