unacceptable

UK: ˌʌnəkˈseptəbl | US: ˌʌnəkˈseptəbl

Definition

  1. adj. not satisfactory or allowable; failing to meet standards

  2. adj. difficult to tolerate or endure

Structure
un <not>accept <receive>able <capable of>
Etymology

The word "unacceptable" combines three morphemes:

  1. "un-" (Old English "un-," meaning "not"), a common negating prefix.
  2. "accept" (Latin "acceptare," from "accipere," meaning "to take or receive").
  3. "-able" (Latin "-abilis," forming adjectives meaning "capable of").
    Originally, "accept" referred to receiving something willingly, and "-able" made it an adjective ("capable of being accepted"). Adding "un-" reversed the meaning to "not capable of being accepted." Over time, it evolved to describe things that fail to meet standards or are intolerable.
Examples

  1. The proposal was deemed unacceptable due to its high cost.

  2. His rude behavior is completely unacceptable in a professional setting.

  3. The food quality was unacceptable, so we complained to the manager.

  4. Delays beyond two hours are unacceptable for this service.

  5. She found the terms of the contract unacceptable and refused to sign.