To rotate the point \( (-4, -6) \) clockwise about the origin by 90 degrees, you can use the following transformation for a clockwise rotation:
\[ (x, y) \rightarrow (y, -x) \]
Using this transformation:
- The original point is \( (-4, -6) \).
- Applying the transformation gives us:
\[ (-6, -(-4)) = (-6, 4) \]
Thus, the new point after rotating \( (-4, -6) \) 90 degrees clockwise around the origin is:
\[ \boxed{(-6, 4)} \]