1. Literally, to be seizing someone or something with a very tight grasp. The bouncer had a firm grip on me as he led me out of the club. I had a firm grip on the wheel to keep the boat on course during the storm.

2. To possess tight and complete control over someone or something. Now that I have a firm grip on the business, I can begin steering it to the success I know it can achieve. Heed my warning—you need to have a firm grip on this new recruit. He's got talent, sure, but he's reckless!