noun
1Botany
rare More fully "white satin flower". Either of two plants of the genus Lunaria, the annual L. annua and the perennial L. rediviva, which have flattened seed pods with a silvery sheen on the inner membrane. Compare "honesty". Also called satin, satin flower.2More fully "white satin moth". The satin moth, Leucoma salicis.
Origin
Late 16th century; earliest use found in John Gerard (c1545–1612), herbalist. From white + satin, probably with allusion to colour and sheen and to smoothness.
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