(one's) back is up

One is angry, hostile, defensive, or irritable, often due to a particular cause. John's back is up now. You shouldn't have brought up the subject of college. It's election season, so my dad's back is up all the time.

Common Names:

Name	Pronounced	Usage
Chan	-	Khmer
Tucker	TUK-ər	English (Modern)
Einion	-	Welsh
River	RIV-ər	English (Modern)
Vanessa	və-NES-ə (English)	English, Italian, Portuguese, German, Dutch
Aiolos	-	Greek Mythology