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not someone's problem

idiom

Definition of not someone's problem

—used to say that someone is not responsible for dealing with something
  • The fact that you're late is not my problem.

Word by Word Definitions

someone play

  1. : some person : somebody

See the full definition of someone
problem play

  1. : a question raised for inquiry, consideration, or solution

  2. : a proposition in mathematics or physics stating something to be done

  3. : an intricate unsettled question

  1. : dealing with a problem of conduct or social relationship

  2. : difficult to deal with

See the full definition of problem

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