An Induration

1. Hardness.
2. Process of becoming hard.
3. (medicine) Hardening of an area of the body as a reaction to inflammation, hyperemia, or neoplastic infiltration.
4. (medicine) An area or part of the body that has undergone such a reaction. Most often this term is used to describe dermatologic findings.
5. (geology) The quality of non-friability; the extent to which a rock does not crumble; rock strength.
6. (geology) The process of the strengthening of rocks by heating, compaction or cementation, or a combination thereof.