add vs threefold

add

verb
  • To make an addition; to augment; to increase; to add on. 

  • To append (e.g. a statement); to say further information; to add on. 

  • To summon minions or reinforcements. 

  • To combine elements of (something) into one quantity. 

  • To give by way of increased possession (to someone); to bestow (on). 

  • To join or unite (e.g. one thing to another, or as several particulars) so as to increase the number, augment the quantity, or enlarge the magnitude, or so as to form into one aggregate. 

  • To sum up; to put together mentally; to add up. 

  • To perform the arithmetical operation of addition. 

noun
  • The addition of a song to a station's playlist. 

  • An act or instance of adding. 

  • An additional enemy that joins a fight after the primary target. 

threefold

verb
  • To make threefold; to triple. 

adj
  • triple 

  • three times as great 

adv
  • by a factor of three 

noun
  • An algebraic variety of dimension 3. 

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