Taproom about noon providing no sustenance (6)
I believe the answer is:
barren
'no sustenance' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.
'taproom about noon' is the wordplay.
'taproom' becomes 'bar' (synonyms).
'about' becomes 're' (common abbreviation for 'with reference to').
'noon' becomes 'n'.
'bar'+'re'+'n'='BARREN'
'providing' acts as a link.
Can you help me to learn more?
(Other definitions for barren that I've seen before include "Unproductive; bleak" , "Producing little vegetation" , "Dull" , "Not producing vegetation or offspring" , "Not fertile, unproductive" .)