I don;t know what goldwave calls it, but there is a feature in many programs where you select a noise only sample, generate a profile from it, then the software uses that to reduce the noise.
http://z-studios.com/blog/2007/03/23/howto-noise-reduction-with-goldwave - description of this in goldwave
The critical thing, is to get a good noise-only sample, I’ve tried this out in other programs, and in a contrived example of voice rendered inaudble by PC fan noise, it retrieved low quality but audible voice, while in a recording with some air conditioner noise, it reduced the noise completely without significant damage to the sound.
