Figure wild anger is something acid (7)
I believe the answer is:
vinegar
'acid' is the definition.
(vinegar is a kind of acid)
'figure wild anger' is the wordplay.
'figure' becomes 'vi' (I can't explain this - if you can you should believe this answer much more).
'wild' indicates an anagram.
'anger' is an anagram of 'negar'.
'vi'+'negar'='VINEGAR'
'is something' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for vinegar that I've seen before include "Pickling condiment" , "Sour liquid used as condiment" , "Condiment - bad temper" , "Sour-tasting liquid as condiment" , "Acetic acid" .)