the.com/mortal coil

means The messy, wearisome business of being a living, breathing human — the body and its hassles that end when you die.

from The phrase comes from Shakespeare's Hamlet (1600s), 'to shuffle off this mortal coil,' where 'coil' meant turmoil or bustle, not a rope or loop — so it originally meant something closer to 'this mortal turmoil' or 'fuss.' Over time, as the older sense of 'coil' faded from everyday English, people naturally reheard it as a coiled rope or chain binding the soul to the body, which is folk reinterpretation rather than Shakespeare's intent — but it stuck, and now it's the meaning everyone uses.