• Webster's Revised Unabridged Dictionary
    • a Subcarboniferous (Geol) Of or pertaining to the lowest division of the Carboniferous formations underlying the proper coal measures. It was a marine formation characterized in general by beds of limestone.
    • ***
Century Dictionary and Cyclopedia
    • subcarboniferous In geology, a name given by some geologists to the mountain-limestone division of the Carboniferous series, or that part of the series which lies beneath the millstone-grit. See carboniferous.
    • ***