cover story vs stratagem

cover story

noun
  • A fictitious account that is intended to hide one's real motive. 

  • A story included in a publication that is highlighted on the front cover. 

stratagem

noun
  • A tactic or artifice designed to gain the upper hand, especially one involving underhanded dealings or deception. 

  • Cunning and artifice in general. 

  • Military deception or artifice. 

  • Specifically, such a tactic or artifice in military operation. 

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