The Collaborative International Dictionary of English v.0.48:

Concrement \Con"cre*ment\, n. [L. concrementum, fr. concrescere.
   See Concrete.]
   A growing together; the collection or mass formed by
   concretion, or natural union. [Obs.]
   [1913 Webster]

         The concrement of a pebble or flint.     --Sir M. Hale
   [1913 Webster]