The Collaborative International Dictionary of English v.0.48:

eggshell \egg"shell`\, a.
   1. of a pale, yellowish-white color; as, an eggshell ceiling
      and light green walls.
      [1913 Webster +PJC]

   2. (Architecture) having a smooth but not glossy texture like
      that of a hen's egg; as, a latex paint giving an eggshell
      finish. Also referred to as matte glaze or non-lustrous
      glaze.
      [PJC]