One cowardly old man nicking lead? (7)
I believe the answer is:
dastard
'one cowardly old' is the definition.
Both the answer and definition are adjectives. Perhaps you can see a link between them that I don't see?
'man nicking lead?' is the wordplay.
'man' becomes 'dad' (I have seen 'Old man' mean 'dad' so perhaps 'man' could also mean 'dad').
'nicking' is an insertion indicator (I've seen this in other clues).
'lead?' becomes 'star' ('star' can be a synonym of 'lead').
'dad' placed around 'star' is 'DASTARD'.
Can you help me to learn more?
(Other definitions for dastard that I've seen before include "Cowardly fellow" , "despicable fellow!" , "Coward" , "contemptible scaredy-cat" .)