noun, na-adjective
ignorance; lack of knowledge; stupidity
Refers to a state of not knowing, lacking information, or being uneducated. Can be used neutrally or as a criticism. Often used in phrases like 無知の知 (knowing one's own ignorance).
彼は自分の無知を恥じた。
He was ashamed of his own ignorance.
その発言は無知もいいところだ。
That remark is the height of ignorance.
Compound of 無 (mu, 'without') and 知 (chi, 'knowledge'). The spelling 無智 uses 智 (wisdom) instead, but the meaning is essentially the same.