Is there an English word meaning “the use of uncommon words”?

Question

Is there an English word meaning "the use of uncommon words" or similar?

Answer 1

It depends on what you mean by "uncommon". Lexiphanicism is the use of excessive terminology, while patavinity is the use of local or provincial words.

(I hope you are not just looking for slang or jargon.)

Answer 2

In the category of similar words, there's sesquipedalian, meaning prone to using long words.

Answer 3

If the uncommon words are being used specifically to obscure meaning, then "obfuscation" might apply.

Answer 4

Depending on how and why you want to use it, logorrhea (also spelled logorrhoea) might do the trick. It doesn't specifically mean using uncommon words but either a. excessive verbosity generally or b. a psychological disorder resulting in incoherent talkativeness.

As an added bonus it conjures up a little hint of a certain other word ending -rrhea.

Answer 5

Obscurantist is related to the 'obfuscation' direction of your question.

Answer 6

If you mean use of words or meanings that are outdated, you might be looking for archaic.

Answer 7

Esoteric Writing

Esoteric (merriam-webster)
1 a : designed for or understood by the specially initiated alone
a body of esoteric legal doctrine — B. N. Cardozo
b : requiring or exhibiting knowledge that is restricted to a small group
esoteric terminology;
broadly : difficult to understand esoteric subjects

esoteric (wiktionary)
1. Understood only by a chosen few or an enlightened inner circle.
The writing in this manual is very esoteric; I need a degree in engineering just to understand it!