Is really mad (7)
I believe the answer is:
seethes
(Other definitions for seethes that I've seen before include "'Boils, with anger perhaps (7)'" , "furious" , "gets agitated" , "gets hot under the collar" , "is angry" .)
I believe the answer is:
seethes
(Other definitions for seethes that I've seen before include "'Boils, with anger perhaps (7)'" , "furious" , "gets agitated" , "gets hot under the collar" , "is angry" .)