Emily Dickinson Lexicon

SO-LID'I-TY, n. [Fr. solidité; L. soliditas.]

1. Firmness; hardness; density; compactness; that quality of bodies which resists impression and penetration; opposed to fluidity. That which hinders the approach of two bodies moving one toward another, I call solidity. – Locke.
2. Fullness of matter; opposed to hollowness.
3. Moral firmness; soundness; strength; validity; truth; certainty; as opposed to weakness or fallaciousness; as, the solidity of arguments or reasoning; the solidity of principles, truths or opinions. – Addison. Prior.
4. In geometry, the solid contents of a body.