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general::
Phrase(s): have a field day
Fig. to experience freedom from one’s usual work schedule; to have a very enjoyable time. (As with children who are released from classes to take part in sports and athletic contests.) • The boss was gone and we had a field day today. No one got anything done. • The air was fresh and clear and everyone had a field day in the park during the lunch hour.
McGrawhill's American Idioms And Phrasal Verbs