imponderable vs transitory

imponderable

adj
  • Not ponderable; without sensible or appreciable weight; incapable of being weighed. 

  • Difficult or impossible to comprehend or evaluate. 

noun
  • An imponderable question. 

  • A factor that cannot be anticipated. 

  • An imponderable substance or body; specifically, in the plural, a name formerly applied to heat, light, electricity, and magnetism. 

transitory

adj
  • Lasting only a short time; temporary. 

  • Of an action: that may be brought in any county 

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