(obsolete) A shellfish which contains mother-of-pearl. / A pearly substance which lines the interior of many shells; mother-of-pearl.

plural of nacre

Resembling mother-of-pearl.

Of, or resembling nacre (mother of pearl). / Exhibiting lustrous or rainbow-like colors.

polar stratospheric cloud

(biochemistry) A matrix protein that is involved in the formation of nacre in molluscs

plural of nacreous cloud