Definitions for diagenesisˌdaɪ əˈdʒɛn ə sɪs
Random House Webster's College Dictionary
di•a•gen•e•sisˌdaɪ əˈdʒɛn ə sɪs(n.)
the physical and chemical changes occurring in sediments between the times of deposition and solidification.
Origin of diagenesis:
All the chemical, physical, and biological changes sediment goes through during and after lithification, not including weathering or other surface changes.