n.
Pronunciation: ˌ mänt-m ə - ' ri-l ə - ˌ n ī t, - ' r ē - ə - ˌ n ī t
Function: noun
Etymology: French, from Montmorillon, commune in western France
Date: 1854
: a soft clayey water-absorbent mineral that is a hydrous aluminum silicate
– mont · mo · ril · lon · it · ic \ - ˌ ri-l ə - ' ni-tik, - ˌ r ē - ə - ' ni- \ adjective