disk vs scutum

disk

noun
  • A type of harrow. 

  • A disc - either a CD-ROM, an audio CD, a DVD or similar removable storage medium. 

  • A ring- or cup-shaped enlargement of the flower receptacle or ovary that bears nectar or, less commonly, the stamens. 

  • Something resembling a disk. 

  • A thin, flat, circular plate or similar object. 

  • An intervertebral disc 

verb
  • To harrow. 

  • To move towards, or operate at, zero blade pitch, orienting the propeller blades face-on to the oncoming airstream and maximising the drag generated by the propeller. 

scutum

noun
  • A scute. 

  • The kneecap. 

  • One of the two lower valves of the operculum of a barnacle. 

  • An oblong shield made of boards or wickerwork covered with leather, with sometimes an iron rim; carried chiefly by the heavily armed infantry of the Roman army. 

  • A shield-like protection, such as the scutum protecting the back of a hard tick (cf. alloscutum, conscutum) 

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