The colic has her all irritable. (8)
I believe the answer is:
choleric
'irritable' is the definition.
(I've seen this in another clue)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for choleric that I've seen before include "Easily angered - cliche or what?" , "Annoyed" , "Bad tempered, irritable" , "Hot-tempered" , "Bad-tempered, irritable" .)