to the backbone

Webster's Dictionary (GCIDE)

1.The column of bones in the back which sustains and gives firmness to the frame; the spine; the vertebral or spinal column. [1913 Webster]

2.Anything like, or serving the purpose of, a backbone. [1913 Webster]

The lofty mountains on the north side compose the granitic axis, or backbone of the country.— Darwin.[1913 Webster]

We have now come to the backbone of our subject.— Earle.[1913 Webster]

3.Firmness; moral principle; steadfastness. [1913 Webster]

Shelley's thought never had any backbone.— Shairp.[1913 Webster]

To the backbone, through and through; thoroughly; entirely. "Staunch to the backbone." --Lord Lytton. [1913 Webster]