tail wagging the dog, the

Idioms  

1. A small or unimportant factor or element governing an important one; a reversal of the proper roles. For example, She found herself explaining the new therapy to her doctor—a real case of the tail wagging the dog. [c. 1900]

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Example Sentences

Far from it being a case of the tail wagging the dog, the collection looked great, even removed from its Japanese element and shrunken to smartphone-size.

From New York Times • May 15, 2017