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 (rā′fīd) also ra·phis (-fĭs)
n. pl. raph·i·des (răf′ĭ-dēz′) or ra··phis·es
One of a bundle of needlelike crystals of calcium oxalate occurring in many plant cells.

[French, sing. of raphides, from New Latin, from Greek rhaphides, pl. of rhaphis, needle, from rhaptein, to sew; see wer- in Indo-European roots.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈræf ɪˌdiz)

needle-shaped crystals, usu. composed of calcium oxalate, that occur in bundles in the cells of many plants.
[1835–45; < New Latin < Greek rhaphídes, pl. of rhaphís needle]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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References in periodicals archive ?
The fruits resemble Indian Maize and develop in a sheath; as they ripen they exude an aroma of Jackfruit but because the sheath contains Calcium Oxalates in the form of needle-like crystals (Raphides) that will lodge in the throat and gums.
Crowther A (2005) Re-viewing raphides: issues with the identification and interpretation of calcium oxalate crystals in microfossil assemblages.
Although the precise toxicity mechanism is unknown, calcium oxalate crystals (raphides) and protease in the idioblast of the plant are considered to be the causes.
In terms of microscopic identification, Dendrobium officinale could be identified by vascular bundle sheath observed under the fluorescence microscopy and the distribution of raphides under normal light microscopy [95].
They are categorized as sands, druses, styloids, raphides, prisms, and crystal sands and exhibit various sizes and shapes [23].
(ST = stomata; SC = substomatal chamber; M = mesophyll; AdE = adaxial epidermis; AbE = abaxial epidermis; X = xylem; P = phloem; BPF = bundle of phloematic fibers; BXF = bundle of xylem fibers; Hi = hipodermis; R = raphides; OC = ornamented cuticle).
The defensive role holds up in some plant species (Ward et al., 1997; Molano-Flores, 2001; Ruiz et al., 2002; Jauregui-Zuniga and Moreno, 2004; Korth et al., 2006; Handley et al., 2007) albeit not in others (Xiang and Chen, 2004; Nagaoka et al., 2010) and some studies indicate that production of COC is increased even as a result of artificial herbivory, as reported for raphides in Sida rhombifolia (Molano-Flores, 2001).
On stipule sections was possible to observe idioblasts with raphides bundles (fig.
Some of these turtles eat large amounts of elephant-ear (Colocassia esculenta), which contains needle-like raphides of oxalic acid monohydrate in its acidic sap.
3h) indicates the occurrence of what are probably tapetal raphides, which also are known from other commelinaceous genera and several other related families (Hardy & Stevenson, 2000a, b; Hardy et al., 2000, 2004; Prychid et al., 2003).