An engineer or scientist, especially one engaged in technological or military research.
A person with specialized knowledge or skills, especially one who is socially awkward; (in a weaker sense) an intellectual; a smart person.
Someone who is an expert in, or devoted to, some specific branch of study or research.
A stenotopic species.
A physician whose practice is limited to a particular branch of medicine or surgery.
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.