event vs optical illusion

event

noun
  • In the event, he turned out to have what I needed anyway. 

  • A point in spacetime having three spatial coordinates and one temporal coordinate. 

  • A possible action that the user can perform that is monitored by an application or the operating system (event listener). When an event occurs an event handler is called which performs a specific task. 

  • One of several contests that combine to make up a competition. 

  • An occurrence; something that happens. 

  • An end result; an outcome (now chiefly in phrases). 

  • A set of some of the possible outcomes; a subset of the sample space. 

  • An episode of severe health conditions. 

  • A prearranged social activity (function, etc.) 

optical illusion

noun
  • An image that is visually deceptive or misleading. 

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