profound

Far-reaching and thoroughgoing in effect especially on the nature of something.

“profound social changes”

Situated at or extending to great depth; too deep to have been sounded or plumbed.

“the profound depths of the sea”

(of sleep) deep and complete.

“fell into a profound sleep”

Coming from deep within one.

“a profound sigh”

Of the greatest intensity; complete.

“a profound silence”

“a state of profound shock”

Showing intellectual penetration or emotional depth.

“the differences are profound”

“a profound insight”