ignoramus

/ɪɡnəˈɹeɪməs/

IPA: /IH0 G N ER0 EY1 M AH0 S/

noun
  1. 1

    A totally ignorant person—unknowledgeable, uneducated, or uninformed; a fool.

noun
  1. 1

    A grand jury's ruling on an indictment when the evidence is determined to be insufficient to send the case to trial.

Source: https://en.wiktionary.org/wiki/ignoramus