odd one out

/AA1 D W AH0 N AW0 T/
noun
  1. 1

    Something or someone in a group that is different or exceptional, that does not fit.

  2. 2

    A visual puzzle where the guesser has to choose which word/picture/symbol etc. does not fit with the others.

Source: https://en.wiktionary.org/wiki/odd%20one%20out