Definition of "specialist"

specialist

/ˈspɛʃəlɪst/

adjective
comparative more specialist, superlative most specialist
1. (Britain) Specialised, involving detailed knowledge of a restricted topic.
  Quotations
  This was a highly specialist job, and it has been very carefully carried out so that it is very hard to see that these windows are now modern replacements.
  2021 December 15, Robin Leleux, “Awards honour the best restoration projects: Special Award: Signal Box Restoration”, in RAIL, number 946, page 57
noun
plural specialists
1. Someone who is an expert in, or devoted to, some specific branch of study or research.
2. (medicine) A physician whose practice is limited to a particular branch of medicine or surgery.
3. (US, military) Any of several non-commissioned ranks corresponding to that of corporal.
4. An organism that is specialized for a particular environment.
5. A stenotopic species.