from
The Collaborative International Dictionary of English v.0.48
Concretion \Con*cre"tion\, n. [L. concretio.]
1. The process of concreting; the process of uniting or of
becoming united, as particles of matter into a mass;
solidification.
[1913 Webster]
2. A mass or nodule of solid matter formed by growing
together, by congelation, condensation, coagulation,
induration, etc.; a clot; a lump; a calculus.
[1913 Webster]
Accidental ossifications or deposits of phosphates
of lime in certain organs . . . are called osseous
concretions. --Dunglison.
[1913 Webster]
3. (Geol.) A rounded mass or nodule produced by an
aggregation of the material around a center; as, the
calcareous concretions common in beds of clay.
[1913 Webster]