Noun
(Jewish law, most commonly) An eruv chatzerot; ritual aggregation of properties that allows Jews observing traditional Shabbat rules to carry burdens across property lines.
Sam is sad that people don't visit him at home on Shabbos because he lives outside the eruv.
(Jewish law) One of the other types of eruv; an eruv tavshilin or eruv techumin.
Source: en.wiktionary.org