A matrix which is not a square matrix is called a..........matrix.

Explanation

To solve the question "A matrix which is not a square matrix is called a..........matrix," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of a Square Matrix**:
- A square matrix is defined as a matrix where the number of rows is equal to the number of columns. For example, a 2x2 matrix or a 3x3 matrix.

2. **Identify What a Non-Square Matrix Is**:
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