... clearing poverty essentially and happy to be advancing (5)
I believe the answer is:
glade
'clearing' is the definition.
(synonyms)
'happy to be advancing' is the wordplay.
'happy' becomes 'glad' (similar in meaning).
'to be advancing' becomes 'e' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'glad'+'e'='GLADE'
'poverty essentially and' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for glade that I've seen before include "wood's open space" , "Clearing in wood" , "Leafy clearing" , "Clearing in a wooded area" , "Woodland opening" .)