Note: There are quite a few phrases and sayings on here with some info on their meanings and origins. To help you with navigating around, we have an alphabetical list that contains numerous expressions, so make use of that if you're looking for one in particular. There's also a sports and animal related phrase page, with a food one coming later. If you are unable to locate a certain expression, then maybe come back another time as additional expressions will be added later on.
KnowYourPhrase.com - Sayings With Their Meanings and Origins
B-Letter Idioms  |  Learn The Meanings For Phrases, Sayings, and Idioms, Along With Their Possible Origins
To make a wrong assumption about someone or something. 

If a person is being falsely accused of something, they might use this phrase to inform the accuser that they are mistaken.
The origin of this phrase is believed to be rooted in dogs and hunting. Dogs are sometimes used during hunting because of their strong sense of smell, their ability to chase and track other animals, and they add a bit of extra security for the hunter.

After spotting another animal, a dog might give chase. The fleeing animal, if it is capable, may decide to climb a tree in order to escape. Dogs, on the other hand, are not so great at climbing trees, so instead they will remain at the trunk of the tree and bark, indicating to the hunter where the fleeing animal is hiding.

Well, obviously dogs can make mistakes and choose the wrong tree. How would a dog slip up and choose the wrong one? Well, there are a few reasons I could think of. Perhaps during the chase the dog was unable to keep up with the fleeing animal and thus lost sight of them, or maybe the dog got distracted along the way and lost focus on what it was chasing. Whatever the case, if a dog fails to pick the right tree, well, then they are literally 'barking up the wrong the tree.'

This expression goes back to at least the early to mid-19th century, where the idiom is already being used in a figurative sense. For example, the Knickerbocker Magazine from 1836 reads:

​    "You've been barking up the wrong tree, cried the Ohioan."
* Jason was barking up the wrong tree when he accused me of being the one who ate the last of the cookies.

* After investigating the crime rates in my neighborhood, I apparently was barking up the wrong tree when I claimed   they had gotten better.

Barking up the wrong tree
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