View your list of saved words. (You can log in using Facebook.)
In geology, a tabular igneous intrusion emplaced parallel to the bedding of the enclosing rock. Although they may have inclined orientations, nearly horizontal sills are most common. Sills may range from a few inches to hundreds of feet thick and up to hundreds of miles long. They include rock compositions of all types.
Variants of SILL
sill or sheet
This entry comes from Encyclopædia Britannica Concise. For the full entry on sill, visit Britannica.com.