A chapel is a place for Eucharistic worship that does not have the full rights of a parish church (it mainly lacks baptismal and burial rights, but from the 13th century onward also the right to hear confessions). Many chapels look like parish churches in miniature, but there is no fixed limit to the size of a chapel, and they cannot necessarily be distinguished architecturally from parish churches.

Chapels can be consecrated spaces within otherwise secular sites such as homes, schools, castles, town halls, hospitals, and gardens. They can also be filial churches subordinated to full parish churches (without the same rights), serving mainly to provide places where people can more conveniently attend mass on Sundays and feast days of obligation.

Not all places with the name "chapel" meet the criteria of this definition. A subsidiary space for a side altar in a church is also called a "chapel" but should not cause the church to be labeled with this designation. In the United Kingdom a chapel can also mean a house of worship belonging to any Protestant congregation outside the Church of England, but that meaning is secondary and should not be used where this definition is applied.