indefinite vs open-ended

indefinite

adj
  • Being an integral without specified limits. 

  • Undecided or uncertain. 

  • 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. 

open-ended

adj
  • Unrestricted by definite limits. 

  • Of a straight draw, made up of four consecutive cards, thus able to be completed by either of two ranks of card. 

  • Adaptable to change. 

  • Permitting a spontaneous or unstructured response. 

  • There will be an open-ended discussion. 

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