uhn ihk sep shə nə bəl
without flaw or fault; beyond objection or criticism.
example: She believed her fiancé was a man of unexceptionable character.
example: Though the student seemed bored and undisciplined in class, the work he handed in was unexceptionable.
Usage note: frequently confused words
It is not surprising that the adjective “unexceptionable” throws many of us off the trail of meaning. It closely resembles the more familiar adjective “unexceptional,” yet means almost the opposite. If we are familiar with the adjective “exceptional,” the morphology of “unexceptional,” the meaningful word parts of which it is formed, is easily, probably automatically analyzed into un- + exceptional, that is, not exceptional.
“Exceptional” is a fairly common word, meaning “unusual or out of the ordinary,” or, by extension, “superior or excellent.” We recognize “exceptional” as a word and don’t need to break it down into “except (verb) +-ion (noun suffix)+ -al (adjective suffix) and then make those word parts add up to “superior or excellent.” Indeed, we might easily lose our grip on the word if we had to do this.
“Unexceptionable” is less transparent. For starters, whether we are conscious of it or not, we are used to -able functioning as an adjective suffix that attaches to verbs (chewable, forgettable, curable) and creates an adjective meaning, roughly, able to be VERBed. There are -able words that deviate from this rule: marriageable and knowledgeable are two often cited by linguists. In these words -able attaches to a noun and their meaning is less predictable.
The base of “unexceptionable” is the adjective “exceptionable,” meaning “likely to be objected to; objectionable.” (Okay, let’s add “objectionable” to the list of anomalous “-able” adjectives.) Knowing the meaning of “exceptionable” helps, but adding “un-” to it does not produce a simple negative, “not likely to be objected to; unobjectionable.” In fact, “unexceptionable” means something closer to “not able to be objected to.” Something that is “without flaw or fault; beyond objection or criticism” is certainly difficult to object to or find fault with.
One way to remember the meaning of “unexceptionable” would be, first, to remember that “exceptionable” belongs in a group with “objectionable” and “questionable.” “Unexceptionable” is the negative of those words, but intensifies the positivity of its meaning.