big dog

noun

informal

: a notably prominent, important, or powerful person, organization, etc. : big gun

Moeller is the defending state champs, so they're the big dog until you knock them off.

—Rick Wilson, Cincinnati Enquirer, 26 Apr. 2013

As I sat in front of my computer, … the big dogs in the newsroom came up to me, one by one, offering nuggets of diehard conservative newsroom wisdom and congratulations.

—Brooke Parkhurst, Belle in the Big Apple: A Novel with Recipes, 2009

Word History

First Known Use

1833, in the meaning defined above

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