From Longman Dictionary of Contemporary Englishunobtainableun‧ob‧tain‧a‧ble /ˌʌnəbˈteɪnəbəl◂/ AWL adjective AVAILABLE#impossible to get Fresh fruit was unobtainable in the winter.
Examples from the Corpus
unobtainable• Your people will be switched off the moment the objective that you have set appears to be unobtainable.• Good apartments to rent had become almost unobtainable.• Many of the items were unobtainable.• The real problems arose when that something was unobtainable.• Fresh fruit is unobtainable at certain times of the year.• But Hegarty has rivals for this seemingly unobtainable Colleen.• In addition such provision promoted stability in the workforce, since workers were reluctant to leave jobs which provided benefits unobtainable elsewhere.• If you set unobtainable objectives you will be seen to have failed even if you do a wonderful job.• Water treatment facilities are non-existent in the area, with chemicals such as chlorine unobtainable to stop the outbreak.• But they had to be humoured before they could be diverted from the unobtainable to the treasure that was actually for sale. 