English Reference
Noun

outlier

n.
C1 Advanced US /ˈaʊtɫaɪɝ/ UK /ˈaʊtlˌaɪə/ out·li·er UK spelling outliers Geology Statistics

n.a value or piece of data that is very different from the others in a group. In geology, it can also describe a rock or mineral that is found far from where it usually appears.

n.a data point that significantly deviates from the rest of a sample or population. In a geological context, it refers to a rock or mineral occurrence that is chemically or geographically distinct from its surrounding area.


SIMPLE

The number 100 is an outlier in this small data set.

CONTEXTUAL

The researcher noticed that one of the test results was an outlier, suggesting a possible error in the measurement process.

COMPLEX

Geologists identified a granite outlier within a field of sedimentary rock, indicating a period of intense tectonic activity that had pushed the intrusive body to the surface.

This may make him something of an outlier in Hollywood.

The Guardian· 13 Aug 2026

Orbit’s first Strange Cargo album seemed like a curio: an outlier in the pop landscape of 1987.

The Guardian· 7 Aug 2026

From outlie + -er.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level C1 · Advanced
Frequency Occasional
Updated