Curt
Etymology
From Latin curtus, "shortened, cut short, mutilated," related to the idea of cutting off. Early English uses could mean literally short or docked. The modern meaning specialized to speech and manner that is cut short in a way that reads as brusque or dismissive.
adjective · /KURT/
Rudely brief in speech or manner.
What it names
The chill of a reply so short it withholds warmth on purpose — a clipped answer that signals displeasure without a single explicit word of it.
Example
His emails had become curt — one line, no greeting — and she wondered what she had done.
Related idea
Terse can be a virtue, meaning economical and pointed; curt is terseness turned cold, brief in a way that feels like a snub.