Strong? Very much so! (6)
I believe the answer is:
mighty
This clue is a quadruple definition!!
'strong?' is the first definition.
(thesaurus)
'very' is the second definition.
(synonyms)
'much' is the third definition.
Both the definition and answer are adjectives. Perhaps they are linked in a way I don't understand?
'so' is the fourth definition.
(thesaurus)
Can you help me to learn more?
(Other definitions for mighty that I've seen before include "Extremely" , "Strong, powerful" , "Having great strength" , "Powerful and great" , "Powerful - exalted" .)