cheer vs perk up

cheer

verb
  • To feel or express enthusiasm for (something). 

  • To gladden; to make cheerful; often with up. 

  • To infuse life, courage, animation, or hope, into; to inspirit; to solace or comfort. 

  • To applaud or encourage with cheers or shouts. 

noun
  • A cry expressing joy, approval or support, such as "hurrah". 

  • That which promotes good spirits or cheerfulness, especially food and entertainment prepared for a festive occasion. 

  • A cheerful attitude; happiness; a good, happy, or positive mood. 

  • A chant made in support of a team at a sports event. 

  • Cheerleading, especially when practiced as a competitive sport. 

perk up

verb
  • to cause to be more lively or enthusiastic. 

  • to become more lively or enthusiastic. 

  • To cause to be more upright, straighten up 

  • His ears perked up when he heard there would be ice cream. 

  • To become more upright 

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