TRAP-ROCKS
\tɹˈapɹˈɒks], \tɹˈapɹˈɒks], \t_ɹ_ˈa_p_ɹ_ˈɒ_k_s]\
Sort: Oldest first
-
[Sw.] (Geol.) Rocks spread out in flat, step-like masses by successive volcanic eruptions ; some hard and crystalline, basalts, greenstones, clinkstones, felstones, etc. ; some soft and earthy, claystones, trap-tuffs. Used generally for any igneous rock indeterminate at first sight.
By Henry Percy Smith