rigid vs tempered

rigid

adj
  • Stiff, rather than flexible. 

  • Fixed, rather than moving. 

  • Uncompromising. 

  • Rigorous and unbending. 

noun
  • An airship whose shape is maintained solely by an internal and/or external rigid structural framework, without using internal gas pressure to stiffen the vehicle (the lifting gas is at atmospheric pressure); typically also equipped with multiple redundant gasbags, unlike other types of airship. 

  • A bicycle with no suspension system. 

tempered

adj
  • Pertaining to the metallurgical process for finishing metals. 

  • Pertaining to the well-tempered scale, where the twelve notes per octave of the standard keyboard are tuned in such a way that it is possible to play music in any major or minor key and it will not sound perceptibly out of tune. 

  • Pertaining to the industrial process for toughening glass, or to such toughened glass. 

  • Having a specified disposition or temper. 

  • Moderated or balanced by other considerations. 

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