(n)a former Celtic kingdom in northwestern England; the name continued to be used for the hilly northwestern region of England including the Lake District and the northern Pennines
a. Pertaining to Cumberland, England, or to a system of rocks found there. [ 1913 Webster ]
Cumbrian system (Geol.), the slate or graywacke system of rocks, now included in the Cambrian or Silurian system; -- so called because most prominent at Cumberland. [ 1913 Webster ]