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in the pipeline

Idioms  
  1. In process, under way, as in The blueprints for the new machine are in the pipeline, but it will take months to get approval . [ Colloquial ; 1940s] Also see in the works .

  2. Budgeted for something but not yet spent, as in There's $5 million more in the pipeline for the city schools . [ Colloquial ; second half of 1900s]