Hot under the collar
Meaning
To be angry, agitated, or visibly annoyed about something.
Origin
In an era when formal attire often included tight, restrictive neckwear, especially for men, the physical manifestation of intense anger became a literal experience. As blood rushed to the face during a fit of pique, the neck and head would visibly flush, heating the skin. A stiff, unyielding collar would then feel suffocatingly warm, constricting around the agitated wearer. This vivid, discomforting sensation—of one's temper literally making them 'hot under the collar'—captured the feeling of being visibly upset, creating a lasting idiom for boiling indignation that endures today.
Examples
- When he discovered his research had been plagiarized, the professor was truly hot under the collar.
- Don't bring up the topic of taxes if you don't want to get Dad hot under the collar.