To rotate a point \((x, y)\) clockwise about the origin by 90 degrees, you can use the transformation:
\[ (x, y) \rightarrow (y, -x) \]
For the given point \((-4, -6)\), we can apply this transformation:
- \(x = -4\)
- \(y = -6\)
Performing the transformation:
\[ (-4, -6) \rightarrow (-6, 4) \]
Thus, the new point after rotating \((-4, -6)\) clockwise 90 degrees about the origin is \((-6, 4)\).
So the answer is:
\(\boxed{(-6, 4)}\)