The definition of a red herring is something intended to distract you or throw you off the track from the truth.(noun)
When a murderer plants a knife in someone else's home to try to throw the police off track, the knife is an example of a red herring.
See red herring in Webster's New World College Dictionary
See red herring in American Heritage Dictionary 4
Origin: From its use to distract hunting dogs from the trail.
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