accidental vs built-in

accidental

noun
  • Those fortuitous effects produced by luminous rays falling on certain objects so that some parts stand forth in abnormal brightness and other parts are cast into a deep shadow. 

  • A property which is not essential; a nonessential; anything happening accidentally. 

  • A sharp, flat, or natural, occurring not at the commencement of a piece of music as the signature, but before a particular note. 

  • Part of a text that has a mainly structural purpose, such as spelling, punctuation, or capitalization. 

adj
  • Occurring sometimes, by chance; occasional. 

  • Happening by chance, or unexpectedly; taking place not according to the usual course of things; by accident, unintentional. 

  • Being a double point with two distinct tangent planes in 4-dimensional projective space. 

  • Adjusted by one or two semitones, in temporary departure from the key signature. 

  • Pertaining to accident and not essence; thus, inessential; incidental; secondary. 

  • Nonessential to something's inherent nature (especially in Aristotelian thought). 

built-in

adj
  • Being an essential and permanent part of something. 

  • Being an included feature that normally comes as an extra. 

  • Constructed as a non-detachable part of a larger structure. 

noun
  • Anything (such as a piece of furniture, or a software feature) that is built in, not added as an extra. 

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