Not incarcerated or in captivity; not under control.(phrase)
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Use "on the loose" in a sentence
"She’s a Vestal Virgin on the loose — she’s Diana, not Venus!"
"They lurched clumsily on the loose footing, but their long riot-clubs were out and winging."
"They nudged and winked one to the other as they looked on the loose fatness of Zlata, her mother, and saw before their eyes Hanneh Hayyeh, with her thick, red lips, and her shape so fat like a puffed-out barrel of yeast."