What is chip on your shoulder?

The phrase "chip on your shoulder" is an idiomatic expression used in English to describe a person who seems to be perpetually angry or resentful, often due to a perceived grievance or sense of inferiority. It suggests that the person is looking for a fight or confrontation, carrying a grievance as though it was a physical chip on their shoulder that they dare someone else to knock off.

The origins of this idiom are somewhat uncertain, but it is believed to have originated in 19th-century America. One theory is that it comes from a practice among boys, or in some accounts, among loggers, who would place a piece of wood on their shoulder and challenge others to knock it off as a way to provoke a fight or demonstrate bravery. Over time, the phrase evolved to represent a broader sense of carrying a grudge or being easily offended.

In modern usage, telling someone they have a "chip on their shoulder" is often not complimentary. It suggests they are overly sensitive or quick to take offense, potentially leading to confrontational or defensive behavior.