Immarces’sible, a. unfading.
Word in the Wild: Only statues, gods and vampires can lay claim to immarcessible beauty.
The etymological origin of this term is an adaptation from the late Latin im- (negative prefix) + marcēscĕre (to fade or whither). The OED provides the Vest-Pocket spelling, but indicates that it is an erroneous spelling of the correct immarcescible.
You can find a complete listing of the Word Blog’s Vest-Pocket Vocabulary entries and learn more about where they come from here.