/mudh"euhr euhv perrl"/ , n.
1. a hard, iridescent substance that forms the inner layer of certain mollusk shells, used for making buttons, beads, etc.; nacre.
adj.
2. of or having the qualities of mother-of-pearl, as being iridescent or pearly: mother-of-pearl buttons.
[ 1500-10; cf. It madreperla, obs. F mère perle ]