perlite

noun

per·​lite ˈpər-ˌlīt 

: volcanic glass that has a concentric structure, appears as if composed of concretions, is usually grayish and sometimes spherulitic, and when heated expands to form a lightweight aggregate used especially in concrete and plaster and as a medium for potting plants

perlitic

ˌpər-ˈli-tik 

adjective

Examples of perlite in a Sentence

Recent Examples on the Web

To enhance drainage, consider adding orchid bark or perlite to the mix. —Sj McShane, Martha Stewart, 7 Jan. 2026

Peat-heavy soils can retain excess moisture, risking plant rot unless amended with pumice, perlite, or sand. —Derek Carwood, Better Homes & Gardens, 5 Jan. 2026

Dip the angled end of the cutting in rooting hormone, then plant it in a pot filled with perlite until roots form. —Karen Brewer Grossman, Southern Living, 1 Jan. 2026

Propagate Texas sage by taking four-inch semi-hardwood cuttings, dipping them in root hormone, and inserting them in a 50% perlite, 50% peat moss mix. —Joshua Siskin, Oc Register, 29 Nov. 2025

Word History

Etymology

French, from perle pearl

First Known Use

1833, in the meaning defined above

Rhymes for perlite

• pearlite

Kids Definition

perlite

noun

per·​lite ˈpər-ˌlīt 

: a glassy mineral of volcanic origin that when expanded by heat forms a lightweight material capable of absorbing liquids (as water)