Word that describes someone that has all possible knowledge in some specific field, like an expert.

  • What's wrong with expert? Also, since you've tagged this as a single word request, you should include a sample sentence demonstrating how the word would be used. Commented Apr 19, 2023 at 5:57
  • 1
    "Professor Dimm is an authority on Jacobean Drama" is stronger than expert. It doesn't quite mean he knows absolutely everything, but he knows so much that whatever he says on the subject is regarded by others as correct, simply because he knows so much about it. If somebody wants to know something they ask him and eveyone accepts his answer.
    – davidlol
    Commented Apr 19, 2023 at 6:57
  • Someone that literally knows everything? Is that even possible? Or just more than anyone else? Do you want a positive term, like genius, or negative, like know-it-all? A fancy word like pantomath or a colloquial one like boffin? Someone who actually uses their knowledge like a scientist or someone who answers questions like an oracle or someone who sits in silence? And do you want an adjective or a noun?
    – Stuart F
    Commented Apr 19, 2023 at 8:56
  • You add some adjective, and refer to a "foremost/leading expert/specialist".
    – Graffito
    Commented Apr 19, 2023 at 9:19
  • Expression or idiom for a person who knows every detail about something is obviously a duplicate when one sees 'expression' defined in the tag to include single words as well as longer strings. But one-word answers were not given (except in comments), in spite of dictionaries including both single words and collocations/fixed phrases/idioms among 'expressions'. Commented Apr 19, 2023 at 10:34

3 Answers 3


"Authority", suggested in comments by @davidlol is better than "pundit" or "specialist".

You can use "the authority" instead of "an authority" to make it stronger.


A likely synonym of "expert" is "pundit". However, it is not a neutral synonym as it carries often ironic connotations. The formal term is "expert".

(SOED) 2 A learned expert or teacher; a person who makes knowledgeable and authoritative pronouncements on current affairs. Freq. iron.

"Specialist" is a neutral synonym of "expert".

(SOED) 2 A person who specially or exclusively studies a subject or a particular branch of a subject.

  • I think of "pundit" as a commentator, perhaps better informed than average, rather than an expert.
    – tgdavies
    Commented Apr 19, 2023 at 11:01

You could call that person a subject matter expert.

Not the answer you're looking for? Browse other questions tagged or ask your own question.