All 5 Uses

profound
in
The Murders in the Rue Morgue
(Auto-generated)

...what is only complex is mistaken (a not unusual error) for what is profound.
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profound = deep or far-reaching in intellect or insight
...my astonishment was profound.
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profound = of greatest intensity or emotional depth
Thus there is such a thing as being too profound.†
The streets were profoundly quiet, as it was nearly three o'clock in the morning.†
Nevertheless, that he failed in the solution of this mystery, is by no means that matter for wonder which he supposes it; for, in truth, our friend the Prefect is somewhat too cunning to be profound.†

Definitions:

(1) (profound as in: profound idea)
deep or far-reaching in intellect or consequence
(2) (profound as in: profound sadness)
of greatest intensity or emotional depth
(3) (meaning too rare to warrant focus)