Definitions of profound:

• adjective:   of the greatest intensity; complete

  Example: "A profound silence"

• adjective:   showing intellectual penetration or emotional depths; from the depths of your being

  Example: "The differences are profound"

• adjective:   situated at or extending to great depth; too deep to have been sounded or plumbed

  Example: "The profound depths of the sea"

• adjective:   coming from deep within one

  Example: "A profound sigh"

• adjective:   far-reaching and thoroughgoing in effect especially on the nature of something

  Example: "Profound social changes"

• adjective:   (of sleep) deep and complete

  Example: "Fell into a profound sleep"