one's back is up
One is offended or angry.
Meaning adapted from Wiktionary, available under CC BY-SA 4.0.
“His back is up because you criticized his work.”
“I tried to offer some helpful advice, but her back was up immediately and she refused to listen.”
“The politician's back was up after the journalist questioned his integrity, leading to a heated and defensive response during the live interview.”
From the physical habit of an angry cat, which arches its back when it finds a situation disagreeable. The idiom records the feline tendency to raise the spine as a defensive posture before an altercation.
- 01
abound in one's own sense
To follow one’s own inclinations and opinions.
- 02
ace up one's sleeve
A surprise advantage of which others are not aware.
- 03
act one's age
To behave in a manner appropriate to one's age.
- 04
act one's age, not one's shoe size
Synonym of act one's age (“to behave in a mature manner; to avoid being childish”).
- 05
afraid of one's own shadow
Exceptionally timid.
- 06
air one's dirty laundry in public
To reveal one's sordid secrets to the public.
- 07
air one's dirty linen in public
Synonym of air one's dirty laundry in public.
- 08
albatross around one's neck
A characteristic, possession, associate, or previous deed that hinders one's ability to succeed.
Last updated August 10, 2026