What is the term for a matrix whose columns are mutually orthogonal, but not necessarily othonormal?
I can't name such a matrix "orthogonal" because that would imply that all columns are unit vectors. By the way, why don't we name these matrices "orthonormal" instead of "orthogonal"? But that fight is over, I guess.
In other words, what is the term for a matrix $A$ for which $A^TA$ is a diagonal matrix, but not necessarily $I$?
One famous example are Hadamard matrices. I'd like to have a shorter term than "matrix whose rows are mutually orthogonal".
For my purpose it would be sufficient to have such a term for square matrices, but I'm also interested in a more general term that also covers non-square matrices.
