perlite noun.
['pǝ:lʌɪt] M19.[French, from
perle PEARL noun1 +
-ITE1.]
A form of obsidian consisting of vitreous globules expandable by heating and used for insulation, plant growth media, etc.
■ perlitic
[-'lɪtɪk] adjective pertaining to or characteristic of perlite;
spec. of or designating a cracked structure in natural glasses caused by contraction during cooling:
L19. [TahlilGaran] English Dictionary ▲