noun ·Rare ·Advanced level

Definitions

Noun

1. 1
   A kind of soil formed in volcanic ash and containing high proportions of glass and amorphous colloidal materials, including allophane, imogolite, and ferrihydrite.

Etymology

From Japanese 暗 (an, “dark”) + 土 (do, “soil”) and Latin solum (“soil”).

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.