unacceptable

Etymology

From Middle English unacceptabylle, equivalent to un- + acceptable.

adj

1. unsatisfactory; not acceptable
   "This shocking report proves once again that we urgently need a radical shake-up of hospital care," said Jeremy Hughes, chief executive of the Alzheimer's Society. "Given that people with dementia occupy a quarter of hospital beds and that many leave in worse health than when they were admitted, it is unacceptable that training in dementia care is not the norm." December 16, 2011, Denis Campbell, “Hospital staff 'lack skills to cope with dementia patients'”, in Guardian
   The British Transport Commission (BTC) was created to own not just the railways, but also London Underground, docks, inland waterways, and some road haulage activities. Its remit was to operate on a break-even basis, with sustained losses unacceptable. March 8 2023, David Clough, “The long road that led to Beeching”, in RAIL, number 978, page 38
2. (linguistics) not conforming to accepted usage

noun

1. Something that is not acceptable.
   Second, the data collected using CASEMAP afford us the opportunity to conduct market segmentation analyses based on the similarity in the pattern of unacceptables and/or the benefits that consumers seek in the category. 1989, Walter A. Henry, Michael Menasco, Hirokazu Takada, New-product Development and Testing, page 106