Except that is what it means. The term is used mainly in certain contexts these days, so you might have gotten the impression that it only applies in those contexts, but 'fiduciary' has a broader meaning.
To quote from Wiki (I know): "[t]he distinguishing or overriding duty of a fiduciary is the obligation of undivided loyalty" and I'd argue that taking on capital imposes just such an obligation, such that trying to hire the people most likely to maximize your investors return is indeed a fiduciary duty, one that implies other duties.
