Clear evidence of injury I had (6)
I believe the answer is:
limpid
'clear' is the definition.
(similar in meaning)
'evidence of injury i had' is the wordplay.
'evidence of injury' becomes 'limp' (I am not sure about this - if you are sure you should believe this answer much more).
'i had' becomes 'i'd' (contraction).
'limp'+'id'='LIMPID'
Can you help me to learn more?
(Other definitions for limpid that I've seen before include "Clear (writing, water)" , "Crystal clear, transparent" , "Completely clear" , "Clear and transparent, water say" , "Calm" .)