Raphide

Part of speech: noun

Definitions

1. A sharp, slender crystal of calcium oxalate or silica formed within plant cells, typically occurring in clusters
2. One of many pointed crystalline structures composed of mineral salts that develop inside the tissues of certain plants
3. A thin, needle-shaped crystal of insoluble salt material deposited in plant cells, often found grouped together in specialized tissues

Etymology: Raphide comes from Ancient Greek "rhaphís," meaning "needle." The word was adopted for the needle-shaped crystals found in certain plant cells, which are typically calcium oxalate. Under a microscope these crystals look like tiny, sharply pointed needles packed together in bundles, and that resemblance is the whole logic of the name. Plant botanists use the term for these bundled crystals, which often sit inside specialised cells and can irritate the mouth and throat of anything that bites into them. The needle image, borrowed from ordinary sewing, was carried over intact into the language of cell biology.

Synonyms: raphia