- lacking in knowledge or training; unlearned: an ignorant man.
- lacking knowledge or information as to a particular subject or fact: ignorant of quantum physics.
- uninformed; unaware.
- due to or showing lack of knowledge or training: an ignorant statement.
- lacking in knowledge or education; unenlightened
- (postpositive often foll by of) lacking in awareness or knowledge (of)ignorant of the law
- resulting from or showing lack of knowledge or awarenessan ignorant remark
late 14c., from Old French ignorant (14c.), from Latin ignorantia, from ignorantem (nominative ignorans), present participle of ignorare “not to know, to be unacquainted; mistake, misunderstand; take no notice of, pay no attention to,” from assimilated form of in- “not, opposite of” (see in- (1)) + Old Latin gnarus “aware, acquainted with” (cf. Classical Latin noscere “to know,” notus “known”), from Proto-Latin suffixed form *gno-ro-, related to gnoscere “to know” (see know).
Form influenced by Latin ignotus “unknown.” Cf. also uncouth. Colloquial sense of “ill-mannered” first attested 1886. As a noun meaning “ignorant person” from mid-15c.