hairline vs imperfect

hairline

noun
  • A very thin fissure. 

  • A fishing line made from hair. 

  • The line along one's forehead where hair starts growing. 

  • A very thin line in writing, drawing, or typography. 

adj
  • very thin, as thin as a hair 

imperfect

noun
  • something having a minor flaw 

  • a tense of verbs used in describing a past action that is incomplete or continuous 

adj
  • not perfect 

  • belonging to a tense of verbs used in describing a past action that is incomplete or continuous 

  • known or expected to be polyphyletic, as of a form taxon. 

  • unisexual: having either male (with stamens) or female (with pistil) flowers, but not with both. 

verb
  • to make imperfect 

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