boff vs howitzer

boff

noun
  • A great success; a hit. 

  • A pupil who works hard; a swot. 

  • A line in a film etc that elicits such a laugh. 

  • A big laugh. 

  • A hit or smack. 

verb
  • to have sexual intercourse (with someone) 

  • To hit; to strike. 

howitzer

noun
  • A powerfully hit shot. 

  • A cannon that combines certain characteristics of field guns and mortars, delivering projectiles with medium velocities, usually with relatively high trajectories; normally a cannon with a tube length of 20 to 30 calibers. 

verb
  • To attack with a howitzer. 

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