glad vs sadden

glad

noun
  • A gladiolus (plant). 

adj
  • Pleased, happy, gratified. 

sadden

verb
  • To darken a color during dyeing. 

  • To make sad or unhappy. 

  • To become sad or unhappy. 

  • To render heavy or cohesive. 

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