quick to become angry or irritable
fractious - tetchy
A ‘fractious’ type of person is somebody who is quarrelsome, easily annoyed, and very stubborn, which makes them difficult to be around in either a social or professional environment. The word can also be used in relation to something that tends to be marked by trouble or acrimonious disagreements, such as a relationship.
I’m not surprised those two are no longer working together. They’ve always had a fractious relationship.
Our teacher’s fractiousness creates a hostile class environment and makes students afraid to engage and ask questions.
The politician answered the journalist rather fractiously. She obviously wasn’t very happy with the question.