1
general::
Phrase(s): run along
to leave. • Please run along and leave me alone. • I have to run along now. Good-bye.
McGrawhill's American Idioms And Phrasal Verbs
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general::
Go away, leave, as in I'll be running along now; I'm already late. This expression is Also used as an imperative to tell someone to go away, as in Run along, children, I have work to do. [Early 1800s]
American Heritage Idioms