Hi Drew,
I tend to think of [link|http://dictionary.reference.com/search?q=industry|industry] as in the sense of definitions of 2 and 3 (i.e. manufacturing). But the oldest meaning of the word comes from the Latin industria which means "diligent activity directed to some purpose\ufffd. So...
Cheers,
Scott.
(who still has trouble with terms like "software industry"...)