IPA: //ˈsuːpərˌspɛʃɪlɪst//
KK: /ˈsuːpərˌspɛʃəlɪst/
A person who has a very specific and advanced level of knowledge or skill in a particular area or subject.
The superspecialist was called in to solve the complex problem that no one else could handle.
Superspecialist → It is formed from "super-" (meaning above or beyond) and "specialist" (from Latin "specialis", meaning particular or specific). The word "superspecialist" refers to someone who is an expert in a very specific area, going beyond the usual level of specialization.
Think of someone who is an expert that is 'above' ('super-') the usual level of expertise in a specific field — that's what a superspecialist is.