Learner's definition of ROLE
1 : the character played by an actor
He plays the role of the villain.
She was given the starring/lead/leading role.
I had a minor/major role in the play.
2 a : a part that someone or something has in a particular activity or situation— usually + in
b : the part that someone has in a family, society, or other group
Everyone had a role [=hand] in winning the game. [=everyone helped to win the game]
The government is taking an active role in improving public schools. [=the government is actively involved in improving public schools]
He had a key role in designing the bridge.
She talked about the roles of exercise and a healthy diet in preventing heart disease.
Newspapers play a major role in determining how people think about politics.
Religion plays an important role in his life. [=religion is very important to him]
After her husband left her, she had to take on the dual role of mother and father for her children.
She likes to play the role of matchmaker with her friends.
She challenged the traditional roles assigned to women.
We'll switch/reverse roles this time, and you can wash the dishes while I dry them.
It was a case of role reversal: the father stayed home with the children while the mother worked.