curse (someone/something) under one’s breath
의미:
(다른 사람이 이해할 수 없는) 매우 흐릿한 소리로 위협하거나 불평하다
예시:
I can't help but curse under my breath as I break off the icicles forming under my nostrils.
I sometimes curse under my breath when I'm angry or annoyed.
The student cursed under his breath at his teachers.