To have a "chip on one's shoulder" is an idiom describing someone who holds a grudge, acts with a persistent angry or unpleasant attitude, and feels wronged or treated unfairly in the past. It suggests a defensive or hostile demeanor, often accompanied by a sense of entitlement or a need to prove oneself.
This idiom traces its roots back to a custom that was known in North America since the early 19th century. There is an 1817 reference by James K. Paulding to "The boyish custom of knocking a chip off the shoulder", referring to a person challenging others to fight by placing a chip of wood on their shoulder and daring anyone to knock it off .
Example:
"He has had a chip on his shoulder ever since he didn't get the promotion he was expecting".
"She acts like she has a chip on her shoulder because she wasn't invited to the party"
- From multiple sources with editing
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One day last December, while I was browsing in an antique store, a brown bear caught my eye. He looked like from a good family but went through some tough times, with one shoe off and an unhappy and cynical facial expression.
I always believe that "inside every cynical person is a disappointed idealist", and the poor bear looked like one of them.
I never bought any 2nd hand toys before, but felt very sorry for the bear and couldn't leave him alone in the store. So I brought him home to be with other bear friends:

It took quite some effort to help him put his shoe on, and unbutton his shirt to make sure there wasn't "a chip on his shoulder":

He looks much more relaxed now, though still has a bit of an attitude of his own. So I call him Chip:

Hope you have time to stop and say hello to Chip the bear, and he wishes you all the very best!
