vermiculite
A hydrous phyllosilicate mineral used in horticulture, construction, and insulation. Technical term; common in gardening and industrial contexts.
Horticultural vermiculite is used by mixing it into soil.
Vermiculite is also used as a thermal insulation material.
Standard kanji spelling for the mineral vermiculite.
Mixed kana-kanji spelling; sometimes used for readability or when the kanji 蛭 is considered difficult.
Mixed katakana-kanji spelling; katakana may be used for the 蛭 part in technical or labeling contexts.
The Japanese name 蛭石 (hiru-ishi) literally means 'leech stone', likely from the way the mineral expands and wriggles when heated, resembling a leech. The English name 'vermiculite' comes from Latin 'vermiculus' (little worm) for the same reason.