On the street in front of my Palo Alto house is a row of crape myrtle trees, which this year are late in blossoming, though other crape myrtles in the neighborhood are in gorgeous bloom; but mine are loaded with buds, and soon will follow.
Crape myrtle is an intriguing compound. To start with, it’s not subsective, but resembloid: crape myrtles are not myrtles, though they (rather vaguely) resemble myrtles. Then there’s the first element, crape (or crepe), which turns out to be, historically, the same word as in the fabric crêpe (or crepe or crape), crêpe (or crepe or crape) paper, the thin pancakes called crêpes, and crepe soles for footwear.
(Then there’s the demi-eggcorn cray paper, which afflicted me as a child.)
1. The plant. The brief version from OED2:
crape-myrtle n. a Chinese shrub, Lagerstrœmia indica, with bright rose-coloured petals of crumpled appearance, cultivated in greenhouses in England, and in gardens in the southern U.S. [cites from 1850 on]
(There is considerable spelling variation: crape myrtle, crepe myrtle, crape-myrtle, crapemyrtle, etc.)
More detail from Wikipedia:
Lagerstroemia …, commonly known as Crape myrtle or Crepe myrtle, is a genus of around 50 species of deciduous and evergreen trees and shrubs native to the Indian subcontinent, southeast Asia, northern Australia and parts of Oceania, cultivated in warmer climates around the world. It is a member of the Lythraceae, which is also known as the Loosestrife family. The genus is named after the Swedish merchant Magnus von Lagerström, who supplied Carolus Linnaeus with plants he collected.
While various species and cultivars are able to fill a wide variety of landscape needs, crepe myrtles are chiefly known for their colorful and long-lasting flowers. Most species of Lagerstroemia have sinewy, fluted stems and branches with a mottled appearance that arises from having bark that sheds throughout the year.
… Flowers are born in summer and autumn in panicles of crinkled flowers with a crepe-like texture. Colors vary from deep purple to red to white, with almost every shade in between.
Here’s a deep pink crape myrtle up close; note the crinkled flowers:
2. Crape myrtles and myrtles. Myrtle is a name applied to a wide variety of plants, some of which aren’t trees or shrubs. The relevant subentries from OED3 (June 2003):
a. Any of various evergreen shrubs or small trees of the genus Myrtus (family Myrtaceae) or formerly included in it; esp. (more fully common myrtle) M. communis, of the Mediterranean region, which has shiny, dark green, leathery, toothless, aromatic leaves and fragrant white flowers, and which is often grown for ornament or for its fragrance. Also, with distinguishing word: any of various varieties of myrtle, esp. the common myrtle.
b. Chiefly with distinguishing word: any of various shrubs of other genera of the family Myrtaceae, or of several unrelated families, thought to resemble the common myrtle in their fragrance, their evergreen leaves, etc.
crape-, fringe-, honey-, sand myrtle, etc.: see the first element.
c. Now usu. with distinguishing word: any of several shrubs of the genus Myrica (family Myricaceae), noted for their aromatic leaves; esp. (more fully bog myrtle, Dutch myrtle, etc.) the sweet gale, M. gale, and (more fully candleberry-myrtle, wax-myrtle) M. cerifera.
d. Austral. More fully Tasmanian myrtle or Australian myrtle, myrtle beech. A tall tree of Victoria and Tasmania, Nothofagus cunninghamii (family Fagaceae), with small, shiny, dark green leaves; the wood of this tree.
e. U.S. Any of several plants that are thought to resemble the common myrtle in some way, esp. (a) the lesser periwinkle, Vinca minor (also †trailing myrtle, running myrtle) [periwinkle is a groundcover]; (b) any of several kinds of Ceanothus (family Rhamnaceae); (c) the California laurel, Umbellularia californica (family Lauraceae)
Sense (a) is the central one; the other senses turn on resemblances between Myrtus (especially M. communis) and other plants. That’s how Lagerstroemia gets to be called myrtle.
3. The crape in crape myrtle. Here we start with French crêpe, which OED2 tells us goes back to 16th cent. crespe < Latin crispa curled. The word comes into English as the name of a crinkly fabric:
crape: An anglicized spelling of modern French crêpe
crêpe: The French word for crape n. (used in that language in the early wider sense, and including crêpe anglais, which is called crape in English), often borrowed as a term for all crapy fabrics other than ordinary black mourning crape. [cites from 1797 on]
crêpe de chine (China crape), a white or other coloured crape made of raw silk. crêpe lisse, smooth or glossy crape, which is not crêpé or wrinkled.
(It’s hard not to admire “crapy fabrics”.)
From this origin, we get (in the mid 19th century) crape myrtle, so-called because of the crinkly, crapy petals of its flowers.
Next along (in English) is
crêpe paper n. a thin crinkled paper resembling crêpe.
[1895 Montgomery Ward Catal. 123/3 Crepe tissue paper.]
1897 Sears, Roebuck Catal. No. 104. 333/1 Assorted imported tissue, 2 pieces crepe paper. [etc.]
Wikipedia expands a bit on this:
Crêpe paper is tissue paper that has been coated with sizing and then creped [or crinkled] to create gathers. [note the verb crepe]
Then come the pancakes and the rubber used for crepe soles:
crêpe: A small, thin pancake. [so-called because they're crisp; English cites from 1907 on] So crêpe Suzette n. (usu. in pl.) a pancake served in a hot sauce, often containing a liqueur.
crêpe: In full crêpe rubber. India-rubber rolled into thin sheets with a corrugated surface. [cites from 1907 on]
crêpe sole: the underside of a shoe covered with crêpe rubber. [cites from 1926-7 on]
4. Cray paper. In my childhood, classroom art and decoration projects regularly used crepe paper — but I understood the name of the material as parallel to Kraft (or kraft) paper:
Kraft paper or kraft is paper or paperboard (cardboard) produced from chemical pulp produced in the kraft process. Pulp produced by the kraft process is stronger than that made by other pulping processes (link)
Since crepe paper is rarely pronounced with / …p + p… / (but has the first /p/ deleted), I heard the compound as Cray (or cray) paper, and when it came time to write it out, used one or another of those spellings (I don’t believe I’d seen it spelled out), to a teacher’s great amusement. So perception — and the model of Kraft paper, whose first element appeared to be a proper name but otherwise made no sense to me — led me to the eggcornish Cray paper. A demi-eggcorn, in the fashion of beyond the pail.
Plenty of other people have come to a similar analysis, as in these examples:
Three Vintage Cray Paper Party Hats (link)
Halloween Hanging Cray Paper Pumpkin 60′s (link)
Q: Why does cray paper burn your tongue? A: Cray paper itself is just thin paper but could be treated with chemicals that might not taste good. (link)
(Crepe paper didn’t make any more sense to me than Cray paper, but spelling is spelling; you just bite the bullet and memorize the spelling.)