downgrade vs overpass

downgrade

noun
  • A downhill gradient on a road or railway. 

  • A reduction of a rating, as a financial or credit rating. 

verb
  • to reduce the official estimate of a storm's intensity. 

  • To reduce in complexity, or remove unnecessary parts; to dumb down. 

  • To place lower in position. 

  • To revert software back to an older version. 

  • To disparage. 

overpass

noun
  • A section of a road or path that crosses over an obstacle, especially another road, railway, etc. 

verb
  • To pass above something, as when flying or moving on a higher road. 

  • To exceed, overstep, or transcend a limit, threshold, or goal. 

  • To disregard, skip, or miss something. 

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