D defs.my
Entry 1 sense Webster, 1913

Geode

/(jē"ōd)/ · Ge·ode · IPA /ˈd͡ʒiː.oʊd/
01 n. A nodule of stone, containing a cavity, lined with crystals or mineral matter.
  1. 1.
    A nodule of stone, containing a cavity, lined with crystals or mineral matter.(Min.)