To relax; to calm down; to stop being angry; to come to one's senses or become more rational.(verb)
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Use "get a grip" in a sentence
"The short, heavyset head of Special Crimes rose to his feet, removed his glasses, and headed toward me as I continued trying to get a grip on my situation."
"Geoff Sanders began to pace around the office as if he were trying to get a grip on his thoughts."
"The warble of the acceleration warning cut through the sudden confused babble, and Ferrol had barely enough time to get a grip on a couch headrest before a burst from the lander's engines shoved the craft forward."