One commercial use is a way of saying place the song on one project (album, mixtape, etc) that you intend to sell or even not sell. As long as it is a release that is commercial use.
If you paying $25 for 1 beat you can get 3 for that price and sell up to 100,000 units of the song using beats from http://www.dirtyscopebeatz.com
Just thought I would mention, and its all royalty free, meaning everything you make you keep, only credits are needed after purchase.