Coin pocketed by engineers, extremely lucky lately (8)
I believe the answer is:
recently
'lately' is the definition.
(I know that lately can be written as recently)
'coin pocketed by engineers extremely lucky' is the wordplay.
'coin' becomes 'cent' (cent is a kind of coin).
'pocketed by' indicates putting letters inside.
'engineers' becomes 're' (Royal Engineers).
'extremely' says to hollow out the word (remove centre letters) (only the extremes of the word are used).
'lucky' with its middle removed is 'ly'.
're'+'ly'='rely'
'cent' put within 'rely' is 'RECENTLY'.
(Other definitions for recently that I've seen before include "Not so long since" , "In the near past" , "Of late" , "Adverb meaning not long ago" , "Happening not long ago" .)