In the johari window, the part of you that you know and have revealed to another person is called the quadrant.

Answer;
In the Johari window , the part of you that you know and have revealed to another person is called the Open Quadrant. 

Explanation;
The Johari model is a model of self-disclosure that explains how self-disclosure that varies from relationship to relationship; the model reflects various stages of relational development, degrees of self-awareness, and others' perceptions. As a relationship becomes more intimate, the Open Quadrant grows larger. 

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