profound

Concise Oxford English Dictionary © 2008 Oxford University Press:
profound/prəˈfaʊnd/

▶adjective (profounder, profoundest)

• 1 very great or intense: profound social changes.

  ■ (of a disease or disability) severe.

• 2 showing great knowledge or insight.

  ■ demanding deep study or thought.

• 3 archaic very deep.

– derivatives
profoundly adverb,
profoundness noun.

– origin ME: from OFr. profund, from L. profundus ‘deep’, from L. pro ‘before’ + fundus ‘bottom’.