A physician whose practice is limited to a particular branch of medicine or surgery.
A stenotopic species.
Someone who is an expert in, or devoted to, some specific branch of study or research.
Any of several non-commissioned ranks corresponding to that of corporal.
An organism that is specialized for a particular environment.
Specialised, involving detailed knowledge of a restricted topic.
One who performs surgery; a doctor who performs operations on people or animals.
A surgeonfish.