無責任

1. Origins, structure, and basic meaning

• Structure: 無責任 is read as むせきにん and is a na-adjective meaning irresponsible or lacking due responsibility for one’s actions or words.
• Basic usage: Spreading an unchecked rumor being irresponsible appears in 噂を広めるのは無責任だ, while an irresponsible remark appears in 無責任な発言.

2. Common pitfalls and similar expressions

• Predicate and noun modification
  • Use 無責任だ as a predicate and 無責任な before a noun.
• Difference from 責任がない
  • Unlike neutrally having no assigned responsibility, this word criticizes someone for acting without due responsibility.