from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A type of blue limestone present in parts of southern England.
- n. A stratigraphic group from the lower Jurassic period, consisting of thin layers of blue limestone.
from the GNU version of the Collaborative International Dictionary of English
- n. 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 Oölite. See the Chart of geology.
from The Century Dictionary and Cyclopedia
- n. In geology, the lower division of the Jurassic.
Originally dialectal, from Old French liois ("compact limestone") (French liais). (Wiktionary)