not an ounce of fat (on somebody)if there is not an ounce of fat on someone, they are thin and usually look healthy (某人身上)没有多余的肉，(某人)瘦得很健康not an ounce of fat (on somebody)• Under their chestnut coats there was not an ounce of fat and their muscles moved without effort.• He was surprised, there was not an ounce of fat on him, but he had shed five pounds.
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