twelve·fold I. \ˈ ̷ ̷|fōld\adjective Etymology:twelve (I) + -fold 1.: having 12 parts or aspects 2.: being 12 times as large, as great, or as many as some understood size, degree, or amount < a twelvefold increase > II. adverb : to 12 times as much or as many : by 12 times < increased twelvefold >