SOA Definition Confusion

After view and review of dozens of dozens of blogs and articles about SOA I concluded that lot of bloggers and writers still defining SOA (Service Oriented Architecture) definition with their own way and every definition are perfect with the respect of respective environments. I want to define SOA in my own words.

If assets are coarse-grained its mean greater flexibility and reusability of assets across different organization department internally and by external business partners as well. In short term all services should be coarse-grained rather then fine-grain. By coarse-grained we achieve loose coupling between services.