add vs include

add

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

  • 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 make an addition; to augment; to increase; to add 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 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. 

include

verb
  • To consider as part of something; to comprehend. 

  • To use a directive that allows the use of source code from another file. 

  • To bring into a group, class, set, or total as a (new) part or member. 

noun
  • A piece of source code or other content that is dynamically retrieved for inclusion in another item. 

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