light-headed vs quicksilver

light-headed

adj
  • Thoughtless; volatile; frivolous. 

  • Dizzy or feeling faint, usually as a result of a drop in blood pressure to the brain; delirious. 

quicksilver

adj
  • Unpredictable, erratic or fickle; mercurial. 

verb
  • To overlay with quicksilver. 

  • To treat with quicksilver. 

noun
  • The metal mercury. 

  • An amalgam of mercury and tin applied to the backs of mirrors, quicksilvering. 

How often have the words light-headed and quicksilver occurred in a corpus of books? (source: Google Ngram Viewer )