Lias

1 definition found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Lias \Li"as\ (l[imac]"as), n. [Cf. F. lias, fr. liais sort of
     limestone, OF. also liois; perh. of Celtic origin, cf. Armor.
     liach, leach, a stone, Gael. leac, W. llech. Cf. {Cromlech}.]
     (Geol.)
     The lowest of the three divisions of the Jurassic period; a
     name given in England and Europe to a series of marine


     limestones underlying the O["o]lite. See the Chart of
     {Geology}.
     [1913 Webster]