The Extended Groth Strip (EGS) is a name given to a survey field
that was selected for searches for high-redshiftgalaxies. Among the surveys using it
have been an HST-based survey and AEGIS.
The region is rectangular, but with edges not aligned
with equatorial coordinates (angled more-or-less 45 degrees,
I believe aligned with galactic coordinates).
Some discoveries are commonly cited with names
using the prefix EGS. Cited:
The Extended Groth Strip is an extended version of
the Groth Strip, a 140 square arcminute region
around coordinates J141700+523000,
which was used for the Groth Strip Survey (GSS).