Renege

To renege means to go back on a promise, undertaking, or contract. I learned this word in recent news on CNN that mentioned president Biden reneged on his promise and pardoned his son Hunter. Other synonyms include revoke, renounce, or abandon. 

Throwing a Fit

 I heard this term first when my son casually mentioned a couple of times "I had a fit" or "I threw a fit" when going over his day's events last night.  To "throw a fit" or "have a fit" means to become very shocked, angry, or worried. Other synonyms are: blow a fuse, blow one's stack, blow up, combust, go ballistic, lose one's temper.