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one's body; one's person
oneself; one's appearance
one's place (in society, etc.); one's position
main part; meat (as opposed to bone, skin, etc.); wood (as opposed to bark); blade (as opposed to its handle); container (as opposed to its lid)
危険から身を守るのが大切だ。
It's important to protect yourself from danger.
不祥事の責任を取って彼は表舞台から身を引いた。
Taking responsibility for the scandal, he withdrew himself from the public stage.
彼は身を犠牲にして人を救った。
He sacrificed himself to save others.