From un- + exceptional.

• IPA^(key): /ˌʌnɪkˈsɛpʃənəl/

• Audio (Southern England):

  (file)

unexceptional (comparative more unexceptional, superlative most unexceptional)

1. Not exceptional.

   Synonyms: lackluster, pedestrian; mundane, plain; see also Thesaurus:mediocre, Thesaurus:normal

   Antonym: exceptional

   • 2004, George Carlin, When Will Jesus Bring the Pork Chops?‎^[1], New York: Hyperion Books, →ISBN, →OCLC, →OL, page 286:

     Uncle Shemp was alarmingly unexceptional. He had no detectable lifestyle, and his only accomplishment was the fact that he was a lifelong member of the general public.

• unexceptionally

• no great shakes