Five years of lewdness and liquor (7)
I believe the answer is:
lustrum
'five years' is the definition.
(I've seen this before)
'lewdness and liquor' is the wordplay.
'lewdness' becomes 'lust' (I can't explain this - if you can you should give a lot more credence to this answer).
'and' is a charade indicator (letters next to each other).
'liquor' becomes 'rum' (rum is a kind of liquor).
'lust'+'rum'='LUSTRUM'
'of' is the link.
Can you help me to learn more?
(Other definitions for lustrum that I've seen before include "several years" , "Five-year period" , "Period of five years" , "Period of 20 ac years" .)