Being acid causes the little woman wild anger (7)
I believe the answer is:
vinegar
'being acid' is the definition.
(I have seen 'Acetic acid ' mean 'vinegar' so perhaps 'acid' could also mean 'vinegar')
'the little woman wild anger' is the wordplay.
'the little woman' becomes 'vi' (short for Violet. I am not sure about the 'little' bit.).
'wild' indicates an anagram.
'anger' with letters rearranged gives 'negar'.
'vi'+'negar'='VINEGAR'
'causes' acts as a link.
Can you help me to learn more?
(Other definitions for vinegar that I've seen before include "Healer with brown paper" , "Pickling agent" , "Acidic condiment" , "Sour-tasting liquid as condiment" , "Salad dressing" .)