also: きょうがい
noun
outside the grounds (of a temple or shrine)
Refers to the area beyond the precincts of a religious site, often used in contrast to 境内 (けいだい, inside the grounds).
その神社の境外には小さな公園がある。
There is a small park outside the grounds of that shrine.
境内と境外の境界がはっきりしていない。
The boundary between inside and outside the temple grounds is not clear.
境内 means inside the grounds of a temple or shrine, the opposite of 境外.
Compound of 境 (boundary) and 外 (outside). The reading けいがい is the standard on'yomi combination; きょうがい is a less common variant.