Illustrated Architecture Dictionary
"A chapel is a holy place or area of worship for Christians, which may be attached to an institution such as a large church, a college, a hospital, a palace, a prison or a cemetery, or may be free-standing and unattached to another building."- Wikipedia: Chapel
"A chapel can either be an alcove with an altar in a large church, or a separate building that is smaller than a full-sized church. Chapels have the same function as church buildings and are equipped the same way, but they are usually dedicated to special use." - Ken Collins
Radiating chapels: Small, semi-circular chapels arranged around the apse of large church. Example: Chartres Cathedral, Chartres, France
Chapel: Definition #7
Webster's New International Unabridged Dictionary, 1957
a. Formerly, a printing office; -- said to have been so called because printing was first carried on in England in a chapel near Westminster Abbey.
b. An association or meeting of the workmen in a printing office, for dealing with matters or questions, affecting their interests.
Example: Roycroft Chapel
Examples from Buffalo architecture:
- Illustration above: Forest Lawn Cemetery Chapel, Crematorium and Columbarium
- Christ Chapel Separate building
- Richmond Chapel, St. Paul's Episcopal Cathedral