UNDERCLAY


Meaning of UNDERCLAY in English

ˈ ̷ ̷ ̷ ̷ˌ ̷ ̷ noun

Etymology: under (III) + clay

: a layer of clay beneath a coal bed often containing fossil roots of coal plants and constituting fireclay

Webster's New International English Dictionary.      Новый международный словарь английского языка Webster.