What are the nuances in various words for "expert"?


In particular, I'm thinking of the words 名人, 玄人, 博士, 専門家, 達人, 巨匠, 通, and 有識者.

I have a vague idea that 玄人 is most often used for an expertise which is
"casual" (eg: このゲームの玄人), and that 博士 generally seems to have qualifications,
though not necessarily a PhD, but beyond that, I don't really have a good
grasp on how these differ.

(I didn't include エキスパート, but that just seems to be used in the normal
katakana contexts from what I've seen).




  * **専門家** (noun): "Expert" in the sense of someone who has academic/professional knowledge and (usually) makes money in that field (e.g., researcher, analyst, lawyer, technologist, physician). Or "specialist" who is especially good at one thing (e.g,. someone who uses only one character in a fighting game).
  * **達人** (noun): "Expert" in the sense of someone who is very skillful at something. This says nothing about one's knowledge level. For example, a ピアノの専門家 doesn't have to be able to play the piano well, whereas a ピアノの達人 is good at playing the piano but may know little about the history of the piano. フランス語の専門家 is someone who professionally studies/teaches French, and フランス語の達人 is a very fluent French speaker.
  * **名人** (noun, suffix): An honorific title like "grand master" (of chess, Tetris, etc). 達人 can be used relatively casually and subjectively, while 名人 tends to be used only for true world leaders (or just [one champion](https://en.wikipedia.org/wiki/Meijin_\(shogi\)) in some fields).
  * **博士** (noun, suffix): "PhD" (academic degree). Sometimes works like "doc(tor)" (as an informal title for a scientist, see [this](https://japanese.stackexchange.com/q/82310/5010)).
  * **巨匠** (noun): "legendary artist/artisan", "maestro". Used only in fields related to art or craftsmanship, and for truly big names like Eric Clapton or Akira Kurosawa.
  * **通** (noun, suffix): An (often non-professional) person who has a good taste/sense and experience about a certain field. Often translated as "connoisseur". 食通 is a gourmet. 経済の専門家 is a professinal economist, whereas a 経済通 may not have an academic-type knowledge but may be good at rumors in Wall Street.
  * **玄人** (noun): 通 and/or 専門家, but sometimes has a connotation like "hardcore; ununderstandable by novices". 専門家向けの道具 is simply a professinal-grade tool, while 玄人向けの道具 may refer to a tricky tool that is not suitable for a beginner. 専門家向けのアニメ makes little sense, while 玄人向けのアニメ is a strange anime that can be enjoyed only by hardcore fans.
  * **有識者** (noun): Anyone who has a deep knowledge about some specific issue. Used almost exclusively in contexts related panel discussions, government advisory boards, etc.




  * **専門家** (noun): "Expert" in the sense of someone who has academic/professional knowledge and (usually) makes money in that field (e.g., researcher, analyst, lawyer, technologist, physician). Or "specialist" who is especially good at one thing (e.g,. someone who uses only one character in a fighting game).
  * **達人** (noun): "Expert" in the sense of someone who is very skillful at something. This says nothing about one's knowledge level. For example, a ピアノの専門家 doesn't have to be able to play the piano well, whereas a ピアノの達人 is good at playing the piano but may know little about the history of the piano. フランス語の専門家 is someone who professionally studies/teaches French, and フランス語の達人 is a very fluent French speaker.
  * **名人** (noun, suffix): An honorific title like "grand master" (of chess, Tetris, etc). 達人 can be used relatively casually and subjectively, while 名人 tends to be used only for true world leaders (or just [one champion](https://en.wikipedia.org/wiki/Meijin_\(shogi\)) in some fields).
  * **博士** (noun, suffix): "PhD" (academic degree). Sometimes works like "doc(tor)" (as an informal title for a scientist, see [this](https://japanese.stackexchange.com/q/82310/5010)).
  * **巨匠** (noun): "legendary artist/artisan", "maestro". Used only in fields related to art or craftsmanship, and for truly big names like Eric Clapton or Akira Kurosawa.
  * **通** (noun, suffix): An (often non-professional) person who has a good taste/sense and experience about a certain field. Often translated as "connoisseur". 食通 is a gourmet. 経済の専門家 is a professinal economist, whereas a 経済通 may not have an academic-type knowledge but may be good at rumors in Wall Street.
  * **玄人** (noun): 通 and/or 専門家, but sometimes has a connotation like "hardcore; ununderstandable by novices". 専門家向けの道具 is simply a professinal-grade tool, while 玄人向けの道具 may refer to a tricky tool that is not suitable for a beginner. 専門家向けのアニメ makes little sense, while 玄人向けのアニメ is a strange anime that can be enjoyed only by hardcore fans.
  * **有識者** (noun): Anyone who has a deep knowledge about some specific issue. Used almost exclusively in contexts related panel discussions, government advisory boards, etc.

