noun, plural lu·nu·lae [loo-nyuh-lee] /ˈlu nyəˌli/.
1. something shaped like a narrow crescent, as the small, pale area at the base of the fingernail.
Also lu·nule [loo-nyool] /ˈlu nyul/.
Origin: 1565–75; < Latin lūnula, equivalent to lūn(a) moon + -ula -ule
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