Si-li´ci-um. A term applied to one of the earths.

Si´nus. [L., a bay.] A cavity, the interior of which is more expanded than the entrance.

Skel´e-ton. [Gr. σκελλω, skellō, to dry.] The aggregate of the hard parts of the body; the bones.

So´di-um. The metallic base of soda

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Sphinc´ter. [Gr. σφιγγω, sphingo, to restrict.] A muscle that contracts or shuts an orifice.

Spi´nal Cord. A prolongation of the brain.

Spi-na´lis. Relating to the spine.

Spine. A thorn. The vertebral column; back-bone.

Spi´nous. Belonging to the spinal column.