Abstruseness of language, a subject, etc.; complexity, intricacy; (in later use) the quality of requiring careful discrimination or of embodying…

An obscure point; a wholly or partially unintelligible expression, piece of writing, etc.

Something which is hard to understand, answer, or explain; a complex or obscure point or question.

Obscure, esoteric, or incomprehensible language; (deliberate) vagueness. Also: an example of this. Obsolete.

In plural. Matters requiring great knowledge or wisdom to be understood; the essential truths, mysteries, or problems of a particular field of…

An obscure or esoteric point or question; something that is abstruse.

figurative. A recondite matter; a profundity.

With the: that which is mysterious, obscure, or arcane.

The quality of being obscure, enigmatic, or hard to interpret; an instance of this.

Pickwickian use of language; an instance of this; a remark made in a Pickwickian sense.

A reference understood by only a limited group of people. Cf. in-joke, n.