To shout, make a loud sound, or perform a sudden, vehement action; to behave in a raucous, frenzied manner.(verb)
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Use "let loose" in a sentence
"Damn it to hell— He let loose with a string of curses as he thrust his gun into his holster and wrapped his arms around her before she could totally lose it and slide bonelessly to the floor."
"As Matt let loose with a series of idiotic dog-coaxing sounds, Carly squinched up her eyes and stared at the parts of the animal she could see."
"His expression went dark as he pointed to something on its back and let loose with some angry-sounding Spanish."