ambush vs surprise

ambush

verb
  • To attack by ambush; to waylay. 

  • To station in ambush with a view to surprise an enemy. 

noun
  • The act of concealing oneself and lying in wait to attack by surprise. 

  • The concealed position or state from which a surprise attack is launched. 

  • An attack launched from a concealed position. 

  • The troops posted in a concealed place, for attacking by surprise; those who lie in wait. 

surprise

verb
  • To attack unexpectedly. 

  • To take unawares. 

  • To do something to (a person) that they are not expecting, as a surprise. 

  • To cause (someone) to feel unusually alarmed or delighted by something unexpected. 

  • To undergo or witness something unexpected. 

  • To cause surprise. 

noun
  • The feeling that something unexpected has happened. 

  • Something unexpected. 

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