characteristic vs incidental

characteristic

adj
  • Being a distinguishing feature of a person or thing. 

noun
  • A distinguishing feature of a person or thing. 

  • For a given field or ring, a natural number that is either the smallest positive number n such that n instances of the multiplicative identity (1) summed together yield the additive identity (0) or, if no such number exists, the number 0. 

  • The integer part of a logarithm. 

  • The distinguishing features of a navigational light on a lighthouse etc by which it can be identified (colour, pattern of flashes etc.). 

incidental

adj
  • Existing tangentially, being a byproduct, a tangent, or a likely consequence. 

  • Entering or approaching, prior to reflection (more frequently incident). 

  • Occurring by chance. 

  • Loosely associated; of limited relevance except indirectly; only accidentally related. 

noun
  • Something that is incidental. 

  • Minor items, not further defined. Incidental expense. 

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