not knowing facts or information that you ought to know:
an ignorant and uneducated man
Political historians are often rather ignorant of economics.
ignorant about➔ see usage note ignore
Many people remain blissfully ignorant about the dangers of too much sun (=happy because they do not know about the dangers).
caused by a lack of knowledge and understanding:
an ignorant remark
3 British English spoken
rude or impolite: