an outcrop of a formation completely surrounded by rocks of younger age.
Lexical Investigations: OutlierOutlier was such a useful and long-established term that, in 1865, geologists coined inlier, so that they could have a contrasting word with the opposite meaning. So why has inlier fallen into disuse today? Maybe it’s because people and things that exist outside the mainstream are inherently more interesting, and therefore are more talked about. Today, outlier can refer to a political maverick, a musical prodigy, …
Origin of inlier
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for inlier
An inlier of these rocks appears in the rising ground east of Dungiven, including dark grey crystalline limestone.
Good slates are quarried at Kilmoganny, in the Silurian inlier on the Slievenaman range.
an outcrop of rocks that is entirely surrounded by younger rocks
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012