D defs.my
Entry 1 sense Webster, 1913

Conchoidal

· Con·choid·al · IPA /kɑŋˈkɔɪ.dəl/
01 a. Having elevations or depressions in form like one half of a bivalve shell; -- applied principally to a surface produced by fracture.
  1. 1.
    Having elevations or depressions in form like one half of a bivalve shell; -- applied principally to a surface produced by fracture.(Min.)