threefold vs twinfold

threefold

adj

  • triple 

  • three times as great 

verb

  • To make threefold; to triple. 

adv

  • by a factor of three 

noun

  • An algebraic variety of dimension 3. 

twinfold

adj

  • Synonym of twofold 

How often have the words threefold and twinfold occurred in a corpus of books? (source: Google Ngram Viewer )