Specialist is defined as an expert in some field or a person who concentrates his or her energies on a specific field.(noun)
A doctor who focuses on care of the heart is an example of a heart specialist.
The definition of specialist is having expert knowledge in a field, or someone or something that concentrates on a limited area.(adjective)
A bookstore that only sells magic and paranormal books is an example of a specialist book store.
See specialist in Webster's New World College Dictionary
See specialist in American Heritage Dictionary 4
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