A lighter of mine (4,4)
I believe the answer is:
davy lamp
'a lighter of mine' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'lighter of mine' is the wordplay.
I cannot really understand how this works, but
'lighter' could be 'lamp' (I've seen this in another clue) and 'lamp' is found within the answer.
The remaining letters 'davy' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for davy lamp that I've seen before include "Former source of mine illumination" , "Coalminer's light" , "Mining illumination" , "First generally-used safety light in coal mines" , "Miner?s portable safety light" .)