Chip

Someone who has a chip on his shoulder is angry all the time. They feel that they have been wronged by the world, so they are always ready for a fight. They are easily offended because they feel that they have been treated unfairly by others, or perhaps they feel inferior. They expect trouble, so they are always ready for it. It can also mean that the person has a grievance about something. Something bad has happened to him, and he might believe it was someone else’s fault. This kind of person is constantly angry about it that it affects his behaviour. In the person’s mind, he is showing how tough he is. You can also use have got. You can also add adjectives to describe the size of the chip.