indefinite vs not clear

indefinite

adj
  • Undecided or uncertain. 

  • Being an integral without specified limits. 

  • Vague or unclear. 

  • Designating an unspecified or unidentified person or thing or group of persons or things 

  • Without limit; forever, or until further notice; not definite. 

noun
  • A word or phrase that designates an unspecified or unidentified person or thing or group of persons or things. 

not clear

How often have the words indefinite and not clear occurred in a corpus of books? (source: Google Ngram Viewer )