D defs.my
Entry 1 sense Webster, 1913

Septarium

· Sep·ta·ri·um · IPA /sɛpˈtɛɹi.əm/
01 n. A flattened concretionary nodule, usually of limestone, intersected within by cracks which are often filled with calcite, barite, or other …
pl. Septaria ((#))
  1. 1.
    A flattened concretionary nodule, usually of limestone, intersected within by cracks which are often filled with calcite, barite, or other minerals.(Geol.)