A type of non-recurring one-off part of Total Revenue which are is not related to primary Business activity.
A typical example are the gains from selling a Fixed Asset or receivables of non-recurring one-off receivables, like gifts or charities.
See also
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Business / Business Administration / Financial Management / Financial Accounting / Profit and Loss (P&L) / Revenue
[ Total Revenue ][ Operating Revenue (Sales) ]
[ Net Income ][ NOPAT] [ Operating Revenue (Sales) ]