ˈrāfə̇d, -ˌfid noun
( -s )
Etymology: back-formation from raphides, plural, from New Latin, irregular from Greek rhaphid-, rhaphis needle, from rhaptein to sew together — more at wrap
: one of the needle-shaped crystals irritating to mucous membrane and usually consisting of calcium oxalate that occur in bundles or sheaflike groups as metabolic by-products of plant cells, are found most abundantly in stems, leaves, and roots of herbs and in the bark of trees, and are discharged when moistened — see crystal sand