stubborn and short-tempered
Describes a person who is both obstinate and quick to anger; often used as a negative character trait. The word is somewhat literary and not common in everyday conversation.
He has a stubborn and short-tempered personality, and gets angry easily.
People who are stubborn and short-tempered tend to clash with those around them.
短気 means 'short-tempered' or 'quick-tempered' and focuses on impatience and irritability, without the stubbornness implied by 一徹短慮.
頑固 means 'stubborn' or 'obstinate' and lacks the short-tempered aspect; 一徹短慮 combines both stubbornness and a quick temper.
A yojijukugo (four-character compound) combining 一徹 (stubborn, obstinate) and 短慮 (short-tempered, quick to anger). The exact historical derivation is uncertain, but the components directly reflect the meaning.