| either of two flat, triangular bones, each forming the back part of a shoulder; a shoulder blade |
| the system by which oxygen is taken into the body; in mammals the system includes the nasal passages, pharynx, trachea, bronchi, and lungs |
circumvallate cir·cum·val·late (sûr'kəm-vāl'āt')
adj.
Surrounded by a ridge or wall-like structure.