Slang. profit or money easily obtained or received unexpectedly. money illegally or dishonestly acquired, especially through graft.
What is the saying about gravy?
It's all gravy Is everything great? You might say that it's all gravy—but why? This fun phrase stems from a traditional English saying that compared life itself to meat and potatoes, while the luxuries were gravy. If “it's all gravy” to you, you're probably enjoying life and its little luxuries.4 Jan 2017