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agile; nimble; light (of foot)
casual (clothing); light (e.g. luggage)
carefree; with limited responsibility
猫が身軽に飛び跳ねた。
The cat leaped nimbly.
彼は身軽な格好で旅に出た。
He set off on his journey traveling light.
全ての責任を果たし終え、彼女は身軽になった。
After finishing all her responsibilities, she felt unburdened.