無む責せき任にん

む

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Meanings

irresponsibility; irresponsible

Used both as a noun and as a な-adjective to describe a person, action, or attitude that lacks a sense of responsibility or accountability.

無む責せき任にんな〈事こと〉an irresponsible (act, remark, attitude, etc.)
彼かれの無む責せき任にんな発はつ言げんが問もん題だいになった。
His irresponsible remark caused a problem.
〈事こと〉を無む責せき任にんに〈動どう詞し〉to do something in an irresponsible way
彼かれは仕し事ごとを無む責せき任にんに放ほうり出だした。
He irresponsibly abandoned his job.
〈人ひと〉の無む責せき任にんさsomeone's irresponsibility (as a trait or behavior)
彼かれの無む責せき任にんさにあきれた。
I was appalled by his irresponsibility.

いい加か減げんN2
いい加減 describes general sloppiness or half-heartedness in doing something, while 無責任 specifically criticizes a failure to be accountable for one's duties or actions.
適てき当とうN4
適当 (in its negative sense) means doing something in a perfunctory, careless way, whereas 無責任 focuses on the moral failing of not owning up to consequences.
不ふ注ちゅう意いN1
不注意 refers to carelessness or inattention that leads to mistakes, while 無責任 refers to a deliberate or habitual disregard for one's duties.

責せき任にんN3
責任 means having a duty or responsibility, while 無責任 describes the lack or disregard of that responsibility.
責せき任にん感かん
無責任 describes being irresponsible or lacking any sense of duty, the opposite of having 責任感.

Compound of 無 (mu, 'without') and 責任 (sekinin, 'responsibility'). The word is a straightforward Sino-Japanese formation.